Thursday, September 30, 2021

difference between trapped and entrapped lungs

 Q: What's the difference between a trapped and an entrapped lung?

Answer: Both trapped and entrapped lungs refer to the condition where lungs do not expand after drainage of the pleural cavity. It can be occupied by effusion, air, or mass. By definition trapped lung refers only to the pleural causes and entrapped lung refers to both pleural and non-pleural causes. Pleural causes are mostly due to adherence to the chest wall due to inflammation. Examples of non-pleural causes are endobronchial obstruction or any interstitial disease. 

Most patients/ with a trapped lung usually have a transudative effusion. An entrapped lung mostly results in an exudative effusion.

#pulmonary


References:

1. John T. Huggins,Fabien Maldonado,Amit Chopra,Najib Rahman,Richard Light, Unexpandable lung from pleural disease : Respirology Volume23, Issue2 February 2018 Pages 160-167 https://doi.org/10.1111/resp.13199 
 Url: https://onlinelibrary.wiley.com/doi/full/10.1111/resp.13199 (last accessed September 29, 2021)

2. Huggins JT, Doelken P, Sahn SA. The unexpandable lung. F1000 Med Rep. 2010;2:77. Published 2010 Oct 21. doi:10.3410/M2-77

Wednesday, September 29, 2021

Escape of Florinef

 Q: What is an "escape phenomenon" of Fludrocortisone?

Answer: Fludrocortisone is a synthetic mineralocorticoid that works by increasing renal sodium and water reabsorption. The overall effect is intravascular volume expansion and increases blood pressure. In prolong use over few weeks, patients develop an "escape phenomenon", which means that overall blood volume hemostasis (balance) goes back to pre-treatment level between intra and extravascular compartments - but its pressor effect stays as it is. This is due to increased peripheral vascular resistance.

#hemodynamics


Reference:

Chobanian AV, Volicer L, Tifft CP, et al. Mineralocorticoid-induced hypertension in patients with orthostatic hypotension. N Engl J Med 1979; 301:68.

Tuesday, September 28, 2021

CRRT and calories

  Q: Continuous renal replacement therapy (CRRT) can be a source of calories to patients in ICU?

A) True

B) False


Answer: A

As a standard of practice, a solution with a concentration of 100 mg/dL of glucose is used during CRRT. Moreover, citrate solution is also added as a normal practice. 

There is a net calorie deliverance of 512 kcal per day on average by the use of glucose and citrate solutions during CRRT. This should be taken into account while calculating patients' total calorie count for the day.

#nephrology

#endocrinology


References:

1.  New AM, Nystrom EM, Frazee E, Dillon JJ, Kashani KB, Miles JM. Continuous renal replacement therapy: a potential source of calories in the critically ill. Am J Clin Nutr. 2017;105(6):1559-1563. doi:10.3945/ajcn.116.139014

Monday, September 27, 2021

sildenafil and left ventricular (LV) contractility

 Q: Sildenafil? (select one) 

A) increases the left ventricular (LV) contractility 

B) reduces the left ventricular (LV) contractility


Answer: B

Sildenafil is a selective type 5 phosphodiesterase (PDE-5) inhibitor. Although its clinical efficacy has been established in Erectile Dysfunction and pulmonary hypertension, so far it has not shown any major benefit in congestive heart failure (CHF). It has three main effects in hemodynamic. 
  • It decreases the pulmonary vascular resistance 
  • It lowers the systemic arterial load 
  • It reduces the left ventricular (LV) contractility
It may improve the peak VO2 in CHF patients with reduced LVEF but no benefit in patients with preserved ejection fraction.

#hemodynamic
#cardiology
#pulmonary
#pharmacology


References:

1. Borlaug BA, Lewis GD, McNulty SE, et al. Effects of sildenafil on ventricular and vascular function in heart failure with preserved ejection fraction. Circ Heart Fail 2015; 8:533. 

2. Zhuang XD, Long M, Li F, et al. PDE5 inhibitor sildenafil in the treatment of heart failure: a meta-analysis of randomized controlled trials. Int J Cardiol 2014; 172:581.

post-pericardiotomy syndrome

Q: In cardiac surgery which of the following has the LEAST occurrence in post-pericardiotomy syndrome? 

A) Pericardial effusion 
B) Cardiac tamponade 
C) Elevated C-reactive protein 
D) Pericardial rub 
E) ECG changes 


Answer: B

Although some level of pericardial effusion occurs in almost 90 percent of the patients after cardiac surgery, overt cardiac tamponade occurs in only about 2 percent of the cases. 

Another interesting phenomenon i.e., the classic ST elevation in all leads of EKG can be noticed only in one-fourth of the patients but high CRP can be obtained in three-fourth of the patients. 

Other common findings are pleuritic chest pain, fever, and pericardial rub.

#surgical-critical-care
#cardiology


Reference:

Imazio M, Brucato A, Rovere ME, et al. Contemporary features, risk factors, and prognosis of the post-pericardiotomy syndrome. Am J Cardiol 2011; 108:1183.

Sunday, September 26, 2021

second IVIG in GBS

Q: For patients with refractory Guillain-Barré syndrome (GBS) who do not respond to the first round of Intravenous immunoglobulin (IVIG), the second course of infusion can be given as "nothing to lose"? 

A) Yes 
B) No


Answer: B

Giving a second course of IVIG to patients who stayed in refractory GBS may harm the patient. It increases thromboembolic complications. There is no added benefit. A recent study published by the Dutch GBS study group showed no benefit, rather harm. 

It was a randomized, double-blind, placebo-controlled trial. Patients were randomly assigned after eligibility for poor prognosis through modified Erasmus Guillain-Barré syndrome Outcome Score. The primary outcome measure was the Guillain-Barré syndrome disability score after 4 weeks. The study spanned over 8 years (Feb 2010 - June 2018). Out of total 337 patients, 93 patients with poor prognosis were included in the modified intention-to-treat analysis: 49 received second course of IVIG, and 44 received placebo. Patients in the treatment group had more serious adverse events (35% vs 16% in the first 30 days), including thromboembolic events. Four patients died in the intervention group (13-24 weeks after randomization).

#neurology


Reference:

Walgaard C, Jacobs BC, Lingsma HF, et al. Second intravenous immunoglobulin dose in patients with Guillain-Barré syndrome with poor prognosis (SID-GBS): a double-blind, randomised, placebo-controlled trial. Lancet Neurol. 2021;20(4):275-283. doi:10.1016/S1474-4422(20)30494-4

Saturday, September 25, 2021

ITP

 Q: Persistent and chronic immune thrombocytopenia is the same thing? (select one)

A) Yes

B) No


Answer: B

It is important to distinguish ITP on the basis of the time period elapsed since diagnosis. This may contribute to the different management of the disease On the basis of time period ITP is divided into three major categories 
  •  Newly diagnosed – Up to 3 months since diagnosis
  •  Persistent – 3-12 months since diagnosis 
  •  Chronic – More than 12 months since diagnosis
Another laboratory clue is to watch changes in other lineages of blood cells, such as WBC and RBC. Any such association excludes the diagnosis of ITP, and a patient may have a new/different pathology.

#hematology


Reference:

Onisâi M, Vlădăreanu AM, Spînu A, Găman M, Bumbea H. Idiopathic thrombocytopenic purpura (ITP) - new era for an old disease. Rom J Intern Med. 2019 Dec 1;57(4):273-283. doi: 10.2478/rjim-2019-0014. PMID: 31199777.

Friday, September 24, 2021

SOB after travel to SE Asia

 Q: 22 years old male born and raised in the United States recently returned after an eight weeks summer trip from Pakistan. Patient has been brought to ED with shortness of breath. CT-chest showed severe pneumonitis. Patient is reported to comply with all required vaccinations and medications recommended for travel to the Southeast Asia region. Which of the following prophylaxis could be responsible for his symptoms?

A) Doxycycline

B) Mefloquine

C) Hepatitis A vaccine

D) Hepatitis B vaccine

E) Azithromycin  


Answer: B

Malarial prophylaxis is highly recommended while traveling to endemic areas known for malaria such as southeast Asia. Mefloquine is one of the most commonly prescribed malarial prophylaxis. A dreaded complication though rare is Mefloquine-induced pneumonitis which fortunately responds to corticosteroids, and gets resolved with the discontinuation of mefloquine. 

Also, caution should be taken in patients while prescribing Mefloquine with cardiac conduction abnormalities and a history of neurologic and/or psychiatric disorders. It may lead to encephalopathy, sleep disturbances with particular reference to strange dreams. 

Mefloquine is usually started 2 weeks prior to the departure date. Symptoms should be watched closely during this period.

#ID
#pulmonary
#neurology
#travel-medicine


References:

1. Chen LH, Wilson ME, Schlagenhauf P. Controversies and misconceptions in malaria chemoprophylaxis for travelers. JAMA 2007; 297:2251. 

2. Meier CR, Wilcock K, Jick SS. The risk of severe depression, psychosis or panic attacks with prophylactic antimalarials. Drug Saf 2004; 27:203. 

3. Katsenos S, Psathakis K, Nikolopoulou MI, Constantopoulos SH. Mefloquine-induced eosinophilic pneumonia. Pharmacotherapy 2007; 27:1767. 

4. Soentjens P, Delanote M, Van Gompel A. Mefloquine-induced pneumonitis. J Travel Med 2006; 13:172.

Thursday, September 23, 2021

Droxidopa

 Q: Droxidopa is potentially an oral form of? (select one)

A) Dopamine

B) Norepinephrine


Answer: B

Droxidopa is chemically a  L-dihydroxyphenylserine. It is also known as DOPS. Relatively less known, it is a synthetic oral amino acid. It is basically a levodopa with an added hydroxyl group. After ingestion, it is decarboxylated to norepinephrine. It is more utilized in outpatient for hypotension particularly in Parkinson's disease. Its utility in ICU has not been established and is still less utilized than midodrine. 

The starting dose is 300 mg per day in the divided dose but can be increased up to 1800 mg per day in divided doses - usually thrice a day. Like midodrine, it can cause supine hypertension. 

It does not work in patients with chronic carbidopa use.

#hemodynamics

#pharmacology


References:

1. Biaggioni I, Arthur Hewitt L, Rowse GJ, Kaufmann H. Integrated analysis of droxidopa trials for neurogenic orthostatic hypotension. BMC Neurol 2017; 17:90. 

2. Kaufmann H, Freeman R, Biaggioni I, et al. Droxidopa for neurogenic orthostatic hypotension: a randomized, placebo-controlled, phase 3 trial. Neurology 2014; 83:328. 

3. Elgebaly A, Abdelazeim B, Mattar O, et al. Meta-analysis of the safety and efficacy of droxidopa for neurogenic orthostatic hypotension. Clin Auton Res 2016; 26:171. 

4. Kaufmann H, Norcliffe-Kaufmann L, Palma JA. Droxidopa in neurogenic orthostatic hypotension. Expert Rev Cardiovasc Ther 2015; 13:875.

Wednesday, September 22, 2021

TOADS-P

 Q: Patients with which of the following poisoning may have an odor like garlic or kerosene? (select one)

A) Isopropyl alcohol 

B) Cyanide 

C) Organophosphates 

D) Hydrogen sulfide 

E) Methyl salicylate


Answer: C

The objective of this question is to emphasize the importance of a proper physical exam to find clues on patients with poisonings. A distinct smell during history taking and examination can help to reach the proper diagnosis.

The list on this topic is long and beyond the scope/space of this pearl. When it comes to the odor of garlic or horseradish, the  mnemonic of "TOADS-P" may help

  • Thallium 
  • Organophosphate
  • Arsenic Poisoning
  • Dimethyl Sulfoxide
  • Sulfur Mustard 
  • Phosphite
Organophosphate may also smell like kerosene.

#toxicology


References:

1. Schiffman SS, Williams CM. Science of odor as a potential health issue. J Environ Qual. 2005 Jan-Feb;34(1):129-38. PMID: 15647542. 

2. Bajracharya SR, Prasad PN, Ghimire R. Management of Organophosphorus Poisoning. J Nepal Health Res Counc. 2016 Sep;14(34):131-138. PMID: 28327676.

Tuesday, September 21, 2021

Atonic seizures

 Q: Atonic seizures usually affect? (select one)

A) upper extremities

B) lower extremities


Answer: B

Atonic seizures are also called drop seizures. Due to the sudden loss of control of mostly the lower extremities, patient collapses to the ground. Clinically, they are hard to diagnosis without EEG. They are also called epileptic negative myoclonus. They mostly identify a local phenomenon like temporal or frontal lobe epilepsy. Besides falling down, some of the intriguing symptoms are head nodding and eyelid drooping.  

The atonic seizures may occur in stroke and central nervous system (CNS) infections. 

#neurology


 References: 

1. So NK. Atonic phenomena and partial seizures. A reappraisal. Adv Neurol. 1995;67:29-39. PMID: 8848976.

2.  Kovac S, Diehl B. Atonic phenomena in focal seizures: nomenclature, clinical findings and pathophysiological concepts. Seizure. 2012 Oct;21(8):561-7. doi: 10.1016/j.seizure.2012.06.004. Epub 2012 Jul 11. PMID: 22789404.

Monday, September 20, 2021

History of appendectomy in ulcerative colitis

 Q: History of early appendectomy is protective in ulcerative colitis (UC)?

A) True

B) False


Answer: A

If a patient has a history of appendectomy at a younger age and/or before the diagnosis, it is protective for the exacerbation both in terms of need for colectomy and/or hospitalizations. 

A review of Swedish data span over 47 years with 63,711 patients decreases the Hazard Ratio (HR) for colectomy particularly if appendectomy is carried out before the age of 20. 

Interestingly, this risk increases with an HR of 1.56 if appendicitis is diagnosed after the diagnosis of UC.

#gastroenterology

#surgical-critical-care


Reference:

Myrelid P, Landerholm K, Nordenvall C, et al. Appendectomy and the Risk of Colectomy in Ulcerative Colitis: A National Cohort Study. Am J Gastroenterol 2017; 112:1311.

Sunday, September 19, 2021

severe anaphylaxis not responsive to epi-injection

 Q: 44 years old obese male with past medical history of asthma and hypertension (HTN) is admitted to ICU after severe anaphylaxis reaction to bee-sting. Patient required intubation and vasopressors to sustain hemodynamics. Patient is known to have previous severe allergies and was carrying epinephrine injection which was promptly injected. Despite administration of epinephrine injection, patient went into severe anaphylaxis. What could be the multiple reasons?

Answer: There are many reasons where epinephrine doesn't work or partially works to prevent anaphylaxis. Patients who are on beta-blockers, alpha-blockers, or angiotensin-converting enzyme inhibitors may not respond well to "epi-injection". Similar reports have been reported with asthmatic patients. 

Another reason in this regard is the improper application of epi-injection. The anterolateral thigh is preferred over other areas as it has relatively less superficial subcutaneous tissue and ample blood supply to absorb epinephrine in the blood. The needle is recommended to pierce an inch to reach the thigh muscle area. Many patients though carry epi-injection but are not properly trained how to apply in panicky situations.

Also, epinephrine should be kept at room temperature to prevent oxidation and inactivation. Carrying epi-injection in hot outdoors for a long period of time may inactivate the injection. 

Our patient in this question has various reasons for not responding to epinephrine. He is obese, may have been on the above-mentioned anti-hypertensives, and has a history of asthma.

#hemodynamics


References:

Simons FER. First-aid treatment of anaphylaxis to food: Focus on epinephrine. J Allergy Clin Immunol 2004; 113:837. Copyright ©2004 Elsevier

Saturday, September 18, 2021

ACE inhibitors induced Visceral angioedema

Case: 54 year old male with past medical history of hypertension which is under control for years with captopril (ACE-inhibitor) presented with severe acute abdominal pain. Patient reports symptoms related to abdomen for years with no specific diagnosis so far. After subsequent workup patient found to have ACE inhibitors induced visceral angioedema.


Discussion: It is not well known that alike angioedema of lips, tongue, face, pharynx, larynx, and subglottic area - ACE inhibitors can also induce visceral angioedema. Due to this lack of knowledge patients may suffer for years with intestinal pain, diarrhea, nausea and vomiting. The most vulnerable area is jejunum followed by the ileum and duodenum. Distal antrum and pylorus of the stomach can be involved too. 

This phenomenon can present as acute abdomen as well (see reference # 2).

#pharmacology

#surgical-critical-care


References:

1. Marmery H, Mirvis SE. Angiotensin-converting enzyme inhibitor-induced visceral angioedema. Clin Radiol 2006; 61:979. 

2.  Bloom AS, Schranz C. Angiotensin-Converting Enzyme Inhibitor-Induced Angioedema of the Small Bowel-A Surgical Abdomen Mimic. J Emerg Med 2015; 48:e127. 

3. Korniyenko A, Alviar CL, Cordova JP, Messerli FH. Visceral angioedema due to angiotensin-converting enzyme inhibitor therapy. Cleve Clin J Med 2011; 78:297.

Friday, September 17, 2021

HDMTX induced ARF

 Q; 32 years old female who was started on high dose methotrexate (HDMTX) 2 weeks ago for  hematologic malignancy  presented with nausea and vomiting. Patient was found to be in acute renal failure (ARF). MTX induced ARF tends to be? (select one)

A) reversible

B) irreversible


Answer: A

MTX induced nephropathy usually occurs in high dose administration referred as HDMTX. Methotrexate precipitates in the renal tubules and directly induce tubular injury. This can be avoided by hydration and alkalinization of the urine. It is advisable to keep urine's PH above 7. Moreover, MTX causes transient compromise of glomerular filtration rate (GFR) after each dose due to afferent arteriolar or mesangial cell constriction. 

Fortunately, HDMTX-induced ARF is usually non-oliguric and kidneys recover their function in two weeks once the MTX is stopped. Patient should be watched for MTX toxicity during this period due to decrease clearance and high plasma level. 

#nephrology

#pharmacology

#toxicology


References:

1. Widemann BC, Adamson PC. Understanding and managing methotrexate nephrotoxicity. Oncologist 2006; 11:694. 

2. Amitai I, Rozovski U, El-Saleh R, et al. Risk factors for high-dose methotrexate associated acute kidney injury in patients with hematological malignancies. Hematol Oncol 2020; 38:584.

3.  Garneau AP, Riopel J, Isenring P. Acute Methotrexate-Induced Crystal Nephropathy. N Engl J Med. 2015 Dec 31;373(27):2691-3. doi: 10.1056/NEJMc1507547. PMID: 26716929.

Thursday, September 16, 2021

RDW

 Q: Which of the following for red cell distribution width (RDW) is a better marker of overall mortality? (select one)

A) high RDW 

B) low RDW


Answer: A

The objective of this question is to direct students towards the importance of laboratory science. Each component of complete blood count (CBC) is of paramount importance. Studies have shown that RDW is a good indirect marker of overall mortality and major pathologies such as cardiac disease, stroke, deep venous thrombosis (DVT), renal and hepatic insufficiencies. Most of the labs report a normal RDW range between 11.5 to 14.5 percent. 

Generally, low RDW is rarely seen. It is either normal or elevated.

#laboratory-science

#hematology


References:

1. Lam AP, Gundabolu K, Sridharan A, et al. Multiplicative interaction between mean corpuscular volume and red cell distribution width in predicting mortality of elderly patients with and without anemia. Am J Hematol 2013; 88:E245. 

2. Horne BD, May HT, Muhlestein JB, et al. Exceptional mortality prediction by risk scores from common laboratory tests. Am J Med 2009; 122:550. 

3. Rezende SM, Lijfering WM, Rosendaal FR, Cannegieter SC. Hematologic variables and venous thrombosis: red cell distribution width and blood monocyte count are associated with an increased risk. Haematologica 2014; 99:194. 

4. Afonso L, Zalawadiya SK, Veeranna V, et al. Relationship between red cell distribution width and microalbuminuria: a population-based study of multiethnic representative US adults. Nephron Clin Pract 2011; 119:c277.

Wednesday, September 15, 2021

symptoms in meningitis

 Q: The classic symptoms of acute bacterial meningitis are more common in? (select one) 

A) Youngs 

B) Adults 


Answer:  B

The objective of this question is to highlight the importance of epidemiology and history taking in clinical medicine. The three classic symptoms, known as the triad of acute bacterial meningitis are 

  • fever 
  • nuchal rigidity, and 
  • change in mental status 

- is relatively more common in patients over the age of 60 years. 

Although nausea is not a part of the classic triad it is usually present. Also, these symptoms sudden onset in nature. 

#ID

#neurology


References:

1. van de Beek D, de Gans J, Spanjaard L, et al. Clinical features and prognostic factors in adults with bacterial meningitis. N Engl J Med 2004; 351:1849. 

2. Weisfelt M, van de Beek D, Spanjaard L, et al. Community-acquired bacterial meningitis in older people. J Am Geriatr Soc 2006; 54:1500. 

3. Attia J, Hatala R, Cook DJ, Wong JG. The rational clinical examination. Does this adult patient have acute meningitis? JAMA 1999; 282:175.

Tuesday, September 14, 2021

Labs in SS

 Q: Which of the following lab best correlates with Serotonin Syndrome (SS)? (select one)

A) Leukocytosis 

B) Creatine phosphokinase (CPK) 

C) Serum bicarbonate 

D) Serum Serotonin level

E) None of the above


Answer: E

The objective of this question is to highlight the fact that serotonin syndrome (SS) is purely a clinical diagnosis and in most cases a diagnosis of exclusion. Diagnosis of SS should be established in conjunction with history, clinical presentation, patient's medications, and physical exam. Serum serotonin level does not correlate with disease severity. 'Hunter's decision rules' is a reliable algorithm for the diagnosis of serotonin toxicity. 

DIC, rhabdomyolysis, lactic acidosis, acute kidney failure, and ARDS are all secondary complications.

#clinical-diagnosis

#neurology


References:

1. Dunkley EJ, Isbister GK, Sibbritt D, Dawson AH, Whyte IM. The Hunter Serotonin Toxicity Criteria; simple and accurate diagnositc decision rules for serotonin toxicity. QJM. 2003;96(9):639. 

2. Scotton WJ, Hill LJ, Williams AC, Barnes NM. Serotonin Syndrome: Pathophysiology, Clinical Features, Management, and Potential Future Directions. Int J Tryptophan Res. 2019;12:1178646919873925. Published 2019 Sep 9. doi:10.1177/1178646919873925 

3. Frank C. Recognition and treatment of serotonin syndrome. Can Fam Physician. 2008;54(7):988-992.

Monday, September 13, 2021

CAP diagnosis

 Q: 65 years old male is admitted to ICU with community-acquired pneumonia (CAP). The presence of infiltrate on chest x-ray is required to establish the diagnosis of CAP? 

A) True 

 B) False 


 Answer: A

The Infectious Diseases Society of America (IDSA) and the American Thoracic Society (ATS) guideline requires the demonstration of an infiltrate on chest imaging to establish the diagnosis of CAP when relevant symptoms are present such as fever, dyspnea, and productive cough. 

Said that these symptoms and infiltrate on chest imaging can be present in other pulmonary as well as non-pulmonary pathologies too. This calls for systematic exclusion of other diseases in differential diagnosis.

#pulmonary

#ID


Reference:

Metlay JP, Waterer GW, Long AC, et al. Diagnosis and Treatment of Adults with Community-acquired Pneumonia. An Official Clinical Practice Guideline of the American Thoracic Society and Infectious Diseases Society of America. Am J Respir Crit Care Med 2019; 200:e45.

Sunday, September 12, 2021

Boxing wound

 Q: 28 years old professional boxer is admitted to trauma unit after a clenched fist injury at his face. On examination, there is a concern for possible wound infection. Trauma and plastic surgeons are on board. Patient reports a life-threatening allergy to penicillin. Which of the following antibiotic can be administered as a monotherapy?

A) Ceftriaxone

B) Clindamycin 

C) Levofloxacin

D) Moxifloxacin 

E) Imipenem-cilastatin


Answer: D

In a boxing wound, all the suspected flora of the skin and mouth flora needs to be covered including anaerobes. Ampicillin-sulbactam or Piperacillin-tazobactam is usually enough as a monotherapy. 

In patients with a severe allergy to penicillin, dual-therapy is required including clindamycin or metronidazole with regularly used fluoroquinolones such as Ciprofloxacin or Levofloxacin. The only fluoroquinolone which can be used as monotherapy is Moxifloxacin. Moxifloxacin has pretty good anaerobic activity. 

It would be prudent to avoid cephalosporin or a carbapenem in this patient with a life-threatening penicillin allergy.


#ID

#pharmacology


Reference:

Stevens DL, Bisno AL, Chambers HF, et al. Practice guidelines for the diagnosis and management of skin and soft tissue infections: 2014 update by the Infectious Diseases Society of America. Clin Infect Dis 2014; 59:147.

Saturday, September 11, 2021

Yersiniosis

 Q: Which of the acute bacterial diarrheas commonly cause pharyngitis, and provides a diagnostic clue with history and clinical exam (hint: pseudoappendicitis)? 

Answer: Yersiniosis 

Y. enterocolitica has a propensity to involve lymphoid tissue like tonsils. It is a good diagnostic clue when put with an outbreak and physical exam as no other acute bacterial diarrhea usually causes pharyngitis. A pharyngeal abscess needs to be ruled out. Progression to Yersinia septicemia is more common in patients with impaired immunity or with iron-overload. Patients with iron overload may very quickly culminate into septic shock if receive blood transfusion while infected. The mortality is high. 

Another interesting presentation is pseudoappendicitis with right lower quadrant pain, fever, vomiting, and leukocytosis. Interestingly, at the OR table surgeons find the appendix normal. The symptoms are due to inflammation around the appendix and terminal ileum and inflammation of the mesenteric lymph nodes.

#ID


References:

1. Tacket CO, Davis BR, Carter GP, et al. Yersinia enterocolitica pharyngitis. Ann Intern Med 1983; 99:40. 

2. Shorter NA, Thompson MD, Mooney DP, Modlin JF. Surgical aspects of an outbreak of Yersinia enterocolitis. Pediatr Surg Int 1998; 13:2. 

3. Guinet F, Carniel E, Leclercq A. Transfusion-transmitted Yersinia enterocolitica sepsis. Clin Infect Dis 2011; 53:583.

Friday, September 10, 2021

Rasburicase and the uric acid measurement

 Q; 42 years old male is transferred to ICU after he developed Tumor Lysis Syndrome (TLS) due to ongoing chemotherapy. Rasburicase is started. The uric acid will be? (select one) 

A) falsely high 

 B) falsely low 


Answer:

After the initiation of the Rasburicase, uric acid cannot be followed reliably to evaluate the response. Rasburicase can spuriously lower the uric acid. Rasburicase causes the enzymatic degradation of uric acid at room temperature in the collected sample. 

Ideally, specific orders should be written to collect the blood sample in a pre-chilled tube. Moreover sample should be placed on ice immediately. Rasburicase induced enzymatic degradation occurs over few hours, so the sample should be run STAT within 3-4 hours. Said that even this precaution may not help to have a reliable value (reference #2).

#oncology

#pharmacology


References:

1. Prescribing information for rasburicase available online at http://products.sanofi-aventis.us/elitek/elitek.html (Accessed on September 03, 2021). 

2. Depreter B, Stove V, Delanghe J. Sampling on ice will not yield reliable uric acid monitoring in rasburicase-treated patients. Clin Biochem. 2016 Dec;49(18):1390-1395. doi: 10.1016/j.clinbiochem.2016.04.011. Epub 2016 Apr 27. PMID: 27129796. 

3. Howard SC, Jones DP, Pui CH. The tumor lysis syndrome [published correction appears in N Engl J Med. 2018 Sep 13;379(11):1094]. N Engl J Med. 2011;364(19):1844-1854. doi:10.1056/NEJMra0904569

Thursday, September 9, 2021

PAL

 Q: 52 years old Japanese male is admitted to ICU with fever, and community-acquired pneumonia. Follow-up workup led to the diagnosis of pyothorax-associated lymphoma (PAL). This is the long-standing complication of? (select one) 

A) Tuberculosis

B) Sarcoidosis

C) Smoking

D) Asbestosis

E) Cystic Fibrosis


Answer: A

PAL is a non-Hodgkin's lymphoma of B-cell phenotype. It evolves in the pleural cavity. So far all of these patients have a history of at least more than 20 years of pyothorax. It is mostly reported in patients who had treatment of artificial pneumothorax for pulmonary tuberculosis or tuberculous pleuritis. 

PAL has no association with immunosuppression. Although it is human herpesvirus type 8 (HHV-8) negative, more than two-thirds of these patients are Epstein-Barr virus (EBV)-positive. 5-year survival is around 20 percent. Most of these patients are Japanese males.

#pulmonary

#oncology

#ID


References:

1. Nakatsuka S, Yao M, Hoshida Y, Yamamoto S, Iuchi K, Aozasa K. Pyothorax-associated lymphoma: a review of 106 cases. J Clin Oncol. 2002 Oct 15;20(20):4255-60. doi: 10.1200/JCO.2002.09.021. PMID: 12377970. 

2. Aozasa K, Takakuwa T, Nakatsuka S. Pyothorax-associated lymphoma: a lymphoma developing in chronic inflammation. Adv Anat Pathol. 2005 Nov;12(6):324-31. doi: 10.1097/01.pap.0000194627.50878.02. PMID: 16330929.

Wednesday, September 8, 2021

COPD - life-threatening

 Q: 58 years old male with COPD exacerbation is admitted to ICU with respiratory rate of more than 30 breaths per minute. His oxygen saturation is 88% on a 35% Venturi mask (VM). ABG showed PCO2 of 58 mmHg. Which of the following will make it a life-threatening respiratory failure? (select one) 

A) use of accessory muscles 

B) acute mental status change


Answer:

As per Global Initiative for Chronic Obstructive Lung Disease (GOLD), COPD patients who require hospitalization are classified into three categories

  • No respiratory failure 
  • Acute nonlife-threatening respiratory failure
  • Acute life-threatening respiratory failure

Contrary to popular belief, the use of accessory muscles of respiration is common and can be supported with non-invasive or invasive mechanical ventilation. Acute change in mental status, high oxygen requirement, severe hypercarbia or pH less than 7.25 makes it life-threatening.

#pulmonary


Reference:

Global Initiative for Chronic Obstructive Lung Disease (GOLD). Global Strategy for the Diagnosis, Management and Prevention of Chronic Obstructive Pulmonary Disease: 2020 Report. http://www.goldcopd.org (Accessed on August 29, 2021).

Tuesday, September 7, 2021

Acetaminophen and ASA organ damage

 Q: Combined ingestion of aspirin and acetaminophen tends to cause more? (select one) 

A) Hepatic failure 

B) Renal failure 


Answer:

In intentional drug overdoses, it is common to ingest two or more drugs together, particularly easily accessible aspirin and acetaminophen. Acetaminophen after oxidative metabolism becomes reactive quinoneimine and gets conjugated to glutathione. On the other hand, aspirin gets converted to salicylate, which gets highly concentrated in the cortex and papillae of the kidney, where it depletes glutathione. Without glutathione depleted, the reactive quinoneimine of acetaminophen produces lipid peroxides causing necrosis and calcification of the papillae. 

Also, aspirin suppresses prostaglandin production resulting in decreased kidney blood flow and so ischemia potentiating the above mechanism.

#toxicology


References:

1. Duggin GG. Combination analgesic-induced kidney disease: the Australian experience. Am J Kidney Dis 1996; 28:S39. 

2. De Broe ME, Elseviers MM. Over-the-counter analgesic use. J Am Soc Nephrol 2009; 20:2098.

Monday, September 6, 2021

HCV in liver transplant

 Q: Patients with Hepatitis C (HCV) viremia who goes for a liver transplant, the reinfection is almost always with the same strain of the virus as prior to the transplant?

A) True

B) False


Answer: A

The major decision in patients with HCV who goes for liver transplant is to establish the timing for the HCV treatment. It can be either before or after the transplant. It is individualized by the transplant team. Various factors come into consideration such as the Child-Pugh class for cirrhosis, and likelihood of meaningful clinical as well as viremic response before transplant. The biggest caveat in treating HCV prior to transplant is the improvement in Model for End-Stage Liver Disease (MELD) score without any clinical improvement. This may harm the patients by increasing their wait time. 

Treatment of HCV after transplant is possible due to safe and effective HCV therapy with direct-acting antivirals (DAAs). The reinfection of donor's liver is almost always with the same strain of the virus as prior to the transplant.

#transplantation

#hepatology


References: 

1. Wright TL, Donegan E, Hsu HH, et al. Recurrent and acquired hepatitis C viral infection in liver transplant recipients. Gastroenterology 1992; 103:317. 

2. Cholankeril G, Joseph-Talreja M, Perumpail BJ, et al. Timing of Hepatitis C Virus Treatment in Liver Transplant Candidates in the Era of Direct-acting Antiviral Agents. J Clin Transl Hepatol. 2017;5(4):363-367. doi:10.14218/JCTH.2017.00007 

3. Chhatwal J, Samur S, Kues B, Ayer T, Roberts MS, Kanwal F, Hur C, Donnell DM, Chung RT. Optimal timing of hepatitis C treatment for patients on the liver transplant waiting list. Hepatology. 2017 Mar;65(3):777-788. doi: 10.1002/hep.28926. Epub 2017 Jan 6. PMID: 27906468; PMCID: PMC5319880.

Sunday, September 5, 2021

Botulism

 Q: Botulism causes? (select one)

A) symmetric ascending weakness 

 B) symmetric descending weakness


Answer: B

The knowledge of the nature of paralysis in botulism is of clinical significance as patients exposed to botulism may be alert, have no fever but may have an acute onset of bilateral cranial neuropathies with symmetric descending weakness. Administration of antitoxin early in the course is of paramount importance. Human-derived botulism immune globulin (called BIG-IV or BabyBIG) is available but is off-label for adults. 

Moreover, intubation may be needed if vital capacity drops below 30 percent of the predicted.

#toxicology


References:

1. Chaudhry R. Botulism: a diagnostic challenge. Indian J Med Res. 2011;134(1):10-12. 

2. Cherington M. Clinical spectrum of botulism. Muscle Nerve. 1998 Jun;21(6):701-10. doi: 10.1002/(sici)1097-4598(199806)21:6<701::aid-mus1 style="color: #0c343d;">3.0.co;2-b. PMID: 9585323.

<701::aid-mus1 style="color: #0c343d;">3. Sobel J. Botulism. Clin Infect Dis. 2005 Oct 15;41(8):1167-73. doi: 10.1086/444507. Epub 2005 Aug 29. PMID: 16163636. 

<701::aid-mus1 style="color: #0c343d;">4. Chalk CH, Benstead TJ, Pound JD, Keezer MR. Medical treatment for botulism. Cochrane Database Syst Rev. 2019 Apr 17;4(4):CD008123. doi: 10.1002/14651858.CD008123.pub4. PMID: 30993666; PMCID: PMC6468196.

Saturday, September 4, 2021

Anton Syndrome

 Q: What is Anton Syndrome?

Answer: 

The full nomenclature is Anton-Babinski syndrome. It occurs in the setting of cortical blindness. Patient denies vision loss (visual anosognosia). To compensate the denial, it is associated with confabulation. 

It can occur under various conditions like stroke, preeclampsia, head trauma, hypertensive encephalopathy or posterior reversible encephalopathy syndrome (PRES), autoimmune diseases involving CNS, Multiple sclerosis, fat embolism, and others.

#neurology



References:

1. Chaudhry FB, Raza S, Ahmad U. Anton's syndrome: a rare and unusual form of blindness. BMJ Case Rep. 2019 Dec 3;12(12):e228103. doi: 10.1136/bcr-2018-228103. PMID: 31801772; PMCID: PMC7001702.

2. Maddula M, Lutton S, Keegan B. Anton's syndrome due to cerebrovascular disease: a case report. J Med Case Rep. 2009;3:9028. Published 2009 Sep 9. doi:10.1186/1752-1947-0003-0000009028

Friday, September 3, 2021

CIRCI

 Q: The reason behind adrenal insufficiency in critical illness is? (select one) 

A) Subnormal corticosteroid production 

B) Increased cellular steroid utilization 


Answer:

During critical illnesses such as septic shock, the reason behind adrenal insufficiency is subnormal corticosteroid production. The hypothalamic-pituitary-adrenal axis stays intact. This is referred to as functional or relative adrenal insufficiency. Another designated term is "critical illness-related corticosteroid insufficiency (CIRCI)." The administration of steroids during pressor-resistant shock despite adequate fluid resuscitation is to balance the altered hypothalamic-pituitary-adrenal (HPA) axis. 

Despite the intact structure of the HPA axis, there are various reasons which lead to adrenal insufficiency. This includes HPA activation which actually increases the circulating cortisol, HPA impairment which causes adrenocortical hyporesponsiveness, and glucocorticoid resistance. 

Unfortunately, clinicians so far failed to reach any consensus definition of CIRCI, and management mostly depends on clinician's judgment and few guidelines.

#hemodynamics


References:

1. Boonen E, Vervenne H, Meersseman P, et al. Reduced cortisol metabolism during critical illness. N Engl J Med 2013; 368:1477. Malerba G, Romano-Girard F, Cravoisy A, et al. Risk factors of relative adrenocortical deficiency in intensive care patients needing mechanical ventilation. Intensive Care Med 2005; 31:388. 

2. Cohen J, Pretorius CJ, Ungerer JP, et al. Glucocorticoid Sensitivity Is Highly Variable in Critically Ill Patients With Septic Shock and Is Associated With Disease Severity. Crit Care Med 2016; 44:1034. 

3. Burry LD, Wax RS. Role of corticosteroids in septic shock. Ann Pharmacother 2004; 38:464.

4. Annane D, Pastores SM, Rochwerg B, et al. Guidelines for the diagnosis and management of critical illness-related corticosteroid insufficiency (CIRCI) in critically ill patients (Part I): Society of Critical Care Medicine (SCCM) and European Society of Intensive Care Medicine (ESICM) 2017. Intensive Care Med 2017; 43:1751.

Thursday, September 2, 2021

Gender in CHA2DS2-VASc score

 Q: In CHA2DS2-VASc score - what is the point allocation for gender? (select one)

A) Male=0, Female=1

B) Male=1, Female=0


Answer: A

CHA2DS2-VASc is a risk stratification score for estimation of stroke risk for nonvalvular atrial fibrillation (AF) in adults. Contrary to popular belief, females have a higher risk of strokes from nonvalvular AF. Said that it needs to acknowledge that not all experts believe in this discrepancy. This sex category (Sc) in CHA2DS2-VASc came from a strong retrospective cohort study of about 100,000 patients (Swedish registry) with AF which found that the risk of ischemic stroke in women was 6.2 percent vs. 4.2 percent per year in males. 

 C = congestive heart failure 
H = Hypertension
Ag e= Age > 75 years (2 points) 
D = Diabetes mellitus
S = Stroke or TIA or thromboembolism - prior 
V = Vascular disease 
Age = 65 to 74 years 
Sc = Sex category 

#cardiology
#neurology


References:

1. Friberg L, Benson L, Rosenqvist M, Lip GY. Assessment of female sex as a risk factor in atrial fibrillation in Sweden: nationwide retrospective cohort study. BMJ 2012; 344:e3522. 

2. Wagstaff AJ, Overvad TF, Lip GY, Lane DA. Is female sex a risk factor for stroke and thromboembolism in patients with atrial fibrillation? A systematic review and meta-analysis. QJM 2014; 107:955.

Wednesday, September 1, 2021

Khorana score

 Q: According to Khorana score which organ cancer has the highest risk of venous thromboembolism (VTE)? 

A) Stomach

B) Lung

C) Lymphoma

D) Gynecologic tumors 

E) Testicular 


Answer:

Khorana score was developed by Dr. Alok A. Khorana at the Cleveland Clinic and was first published in 2008. It estimates the risk of VTE in cancer patients. It is a validated score and has been re-tested with subsequent trials. It takes into account five factors to determine the risk of VTE 

  • Site of the primary tumor 
  • Pre-chemotherapy platelet count 
  • Hemoglobin level 
  • Pre-chemotherapy WBC count 
  • BMI 

In Khorana score stomach and pancreas cancers were found to have the highest risk of VTE. Said that patients with brain tumors and myeloma were excluded from the trial published in 2008. 

Khorana score is available via various search engines.  Later on, CASSINI and AVERT trials looked into thromboprophylaxis in cancer patients.  

#oncology

#hematology


References:

1. Khorana AA, Kuderer NM, Culakova E, et al. Development and validation of a predictive model for chemotherapy-associated thrombosis. Blood 2008; 111:4902. 

2. Ay C, Dunkler D, Marosi C, et al. Prediction of venous thromboembolism in cancer patients. Blood 2010; 116:5377. 

3. Mandala M, Clerici M, Corradino I, et al. Incidence, risk factors and clinical implications of venous thromboembolism in cancer patients treated within the context of phase I studies: the 'SENDO experience'. Ann Oncol 2012; 23:1416.

4. Langhorne P, Wu O, Rodgers H, Ashburn A, Bernhardt J. A Very Early Rehabilitation Trial after stroke (AVERT): a Phase III, multicentre, randomised controlled trial. Health Technol Assess. 2017 Sep;21(54):1-120. doi: 10.3310/hta21540. PMID: 28967376; PMCID: PMC5641820.

5. Khorana AA, Soff GA, Kakkar AK, Vadhan-Raj S, Riess H, Wun T, Streiff MB, Garcia DA, Liebman HA, Belani CP, O'Reilly EM, Patel JN, Yimer HA, Wildgoose P, Burton P, Vijapurkar U, Kaul S, Eikelboom J, McBane R, Bauer KA, Kuderer NM, Lyman GH; CASSINI Investigators. Rivaroxaban for Thromboprophylaxis in High-Risk Ambulatory Patients with Cancer. N Engl J Med. 2019 Feb 21;380(8):720-728. doi: 10.1056/NEJMoa1814630. PMID: 30786186.