Dig in pregnancy

Q: Digoxin is contraindicated in pregnancy?

A) Yes

B) No

Answer: B 

Digoxin is one of the unique medicines that is given to the mother for fetal cardiac indications. It crosses the placenta without causing fetal harm or teratogenicity. Moreover, it can be used in lactation for maternal cardiac indications.

It is mostly used to treat sustained fetal tachyarrhythmias, such as supraventricular tachycardia (SVT) and atrial flutter, and to prevent hydrops fetalis.

#ob-gyn

#pharmacology

#pediatrics

#cardiology

References:

1. Hauptman PJ, Kelly RA. Digitalis. Circulation 1999; 99:1265.

2. Wang C, Zhao L, Shao S, Yu H, Zhou S, Li Y, Zhu Q, Liu X, Duan H, Liu H, Hua Y, Zhou K. Transplacental digoxin treatment for fetal supraventricular arrhythmias: Insights from Chinese fetuses. Chin Med J (Engl). 2025 Jun 20;138(12):1499-1501. doi: 10.1097/CM9.0000000000003583. Epub 2025 Apr 9. PMID: 40204513; PMCID: PMC12180843.

3. Soyka LF. Digoxin: placental transfer, effects on the fetus, and therapeutic use in the newborn. Clin Perinatol. 1975 Mar;2(1):23-35. PMID: 1102216.

catamenial epilepsy

Q: Catamenial epilepsy occurs more frequently in which phase of the menstrual cycle?

A) early 

B) mid

C) late

Answer: C

Catamenial epilepsy can best be predicted by keeping a seizure diary. In a regular menstrual cycle, estrogen levels peak during mid-cycle (without conception) and drop just before the onset of menses. During this period, most seizure clusters are reported. Although a periovulatory seizure may occur. 

Standard treatment of seizures should be sufficient.

Use of Clobazam during the vulnerable phase of the menstrual cycle has shown some promise. 20 to 30 mg of Clobazam per day for 10 days during the high-risk phase of the menstrual cycle has been found to be effective. Intermittent lorazepam may also be used in the vulnerable period.

Some experts recommend the use of an adjunctive continuous estrogen-progestin contraceptive as hormonal prophylaxis for catamenial epilepsy, though evidence is weak for such practice. Other recommended treatments, but with very limited data, are acetazolamide, gonadotropin analogs, and neurosteroids (ganaxolone).

#neurology

#ob-gyn

References:

1. Herzog AG, Fowler KM, Sperling MR, et al. Variation of seizure frequency with ovulatory status of menstrual cycles. Epilepsia 2011; 52:1843.

2. Maguire MJ, Nevitt SJ. Treatments for seizures in catamenial (menstrual-related) epilepsy. Cochrane Database Syst Rev 2021; 9:CD013225.

3. Herzog AG, Fowler KM, Smithson SD, et al. Progesterone vs placebo therapy for women with epilepsy: A randomized clinical trial. Neurology 2012; 78:1959.

4. Feely M, Calvert R, Gibson J. Clobazam in catamenial epilepsy. A model for evaluating anticonvulsants. Lancet 1982; 2:71.

5. Ansell B, Clarke E. Acetazolamide in Treatment of Epilepsy. Br Med J 1956; 1:650.

6. Reddy DS. Neurosteroid replacement therapy for catamenial epilepsy, postpartum depression and neuroendocrine disorders in women. J Neuroendocrinol 2022; 34:e13028.

PP and Carbs

Q: A high-carbohydrate load is recommended in patients who present with hypokalemic Periodic paralysis (PP), including thyrotoxic PP.

A) True

B) False

Answer: B

PP attacks in hypokalemic thyrotoxic patients result from increased release of epinephrine or insulin, causing intracellular potassium shifts and low serum potassium levels. Known inciting events are:

• strenuous physical activity
• stress
• high-carbohydrate load (answer for above Q)
• cold exposure
• infection
• alcohol intake
• pulse corticosteroid therapy
• beta-2 adrenergic bronchodilator 
• menses 
• exogenous epinephrine or insulin
• acetazolamide
• thyroid supplements 

#electrolytes

References:

1. Hsieh MJ, Lyu RK, Chang WN, et al. Hypokalemic thyrotoxic periodic paralysis: clinical characteristics and predictors of recurrent paralytic attacks. Eur J Neurol 2008; 15:559.

2. Qing G, Zakaria WNA, Rom FZM, Nik WNFHW, Zulkeflee HA, Rahim SNA. Thyrotoxic Hypokalemic Periodic Paralysis: Pathophysiological Mechanisms. Endocrinol Metab (Seoul). 2025 Dec;40(6):821-829. doi: 10.3803/EnM.2025.2554. Epub 2025 Dec 11. PMID: 41376301; PMCID: PMC12765881.

3. Chang CC, Cheng CJ, Sung CC, et al. A 10-year analysis of thyrotoxic periodic paralysis in 135 patients: focus on symptomatology and precipitants. Eur J Endocrinol 2013; 169:529.

MH and gender

Q: Malignant Hyperthermia (MH) is disproportionally high in? - select one

A) males

B) females

Answer: A

The male-to-female ratio for MH is 2:1. The obvious explanation is the likely higher skeletal mass in males, though it does not fully account for the high prevalence in males. Moreover, children less than 19 years of age are more prone to develop MH.

#anesthesia

References:

1. Brady JE, Sun LS, Rosenberg H, Li G. Prevalence of malignant hyperthermia due to anesthesia in New York State, 2001-2005. Anesth Analg 2009; 109:1162.

2. Larach MG, Gronert GA, Allen GC, et al. Clinical presentation, treatment, and complications of malignant hyperthermia in North America from 1987 to 2006. Anesth Analg 2010; 110:498.

3. Rosenberg H, Davis M, James D, et al. Malignant hyperthermia. Orphanet J Rare Dis 2007; 2:21.

4. Rosenberg H, Pollock N, Schiemann A, Bulger T, Stowell K. Malignant hyperthermia: a review. Orphanet J Rare Dis. 2015 Aug 4;10:93. doi: 10.1186/s13023-015-0310-1. PMID: 26238698; PMCID: PMC4524368.

Metronidazole and disulfiram-like reactions.

Q: Metronidazole should be avoided with alcohol intake as it may cause disulfiram-like reactions.

A) True

B) False

Answer: B

Although it was once believed that metronidazole could cause disulfiram-like reactions with ETOH, this was based on a few weak reports. Evidence failed to prove any such association. The United States Centers for Disease Control and Prevention (CDC) Sexually Transmitted Infection Guidelines in 2021 removed abstaining from alcohol while taking metronidazole.

Metronidazole does not inhibit alcohol metabolism in the liver or increase blood acetaldehyde production, the basis for disulfiram-like reactions. It is suggested that metronidazole and ethanol both, independently, increase brain serotonin levels, potentially giving an impression of disulfiram-like reactions.

# pharmacology

References:

1. Visapää JP, Tillonen JS, Kaihovaara PS, Salaspuro MP. Lack of disulfiram-like reaction with metronidazole and ethanol. Ann Pharmacother 2002; 36:971.

2. Tillonen J, Väkeväinen S, Salaspuro V, et al. Metronidazole increases intracolonic but not peripheral blood acetaldehyde in chronic ethanol-treated rats. Alcohol Clin Exp Res 2000; 24:570.

3. Karamanakos PN, Panteli ES, Marselos M. Comment on 'Can Metronidazole Cause a Disulfiram-Like Reaction? A Case-Control Study Propensity Matched By Age, Sex and Ethanol. WMJ 2024; 123:3.

4. Workowski KA, Bachmann LH, Chan PA, et al. Sexually Transmitted Infections Treatment Guidelines, 2021. MMWR Recomm Rep 2021; 70:1.

5. Feldman R, Jaszczenski R. Can Metronidazole Cause a Disulfiram-Like Reaction? A Case-Control Study Propensity Matched by Age, Sex, and Ethanol Concentration. WMJ 2023; 122:171.

Acute HIV on PrEP

Q: What's the caveat of diagnosing HIV in patients who are using pre-exposure prophylaxis (PrEP) for HIV?

Answer: Unreliable clinical signs and routine HIV screening test

Patients who are on pre-exposure prophylaxis (PrEP) due to their lifestyle may not develop full-blown acute HIV symptoms on initial contraction, but may have mild symptoms called pauci-symptomatic acute HIV. Cardinal acute HIV symptoms such as fever and rash are usually absent, and there may be no pharyngitis or diarrhea. To make things more complicated, routine HIV screening with the antigen/antibody test may not be reliable. Diagnosis can be made by history, exposure, keeping a high clinical suspicion, and HIV RNA as the screening tool.

#ID

References:

1. Landovitz RJ, Delany-Moretlwe S, Fogel JM, et al. Features of HIV Infection in the Context of Long-Acting Cabotegravir Preexposure Prophylaxis. N Engl J Med 2024; 391:1253.

2. Moschese D, Lazzarin S, Colombo ML, Caruso F, Giacomelli A, Antinori S, Gori A. Breakthrough Acute HIV Infections among Pre-Exposure Prophylaxis Users with High Adherence: A Narrative Review. Viruses. 2024 Jun 12;16(6):951. doi: 10.3390/v16060951. PMID: 38932243; PMCID: PMC11209220.

3. Elliott T, Sanders EJ, Doherty M, Ndung'u T, Cohen M, Patel P, Cairns G, Rutstein SE, Ananworanich J, Brown C, Fidler S. Challenges of HIV diagnosis and management in the context of pre-exposure prophylaxis (PrEP), post-exposure prophylaxis (PEP), test and start and acute HIV infection: a scoping review. J Int AIDS Soc. 2019 Dec;22(12):e25419. doi: 10.1002/jia2.25419. PMID: 31850686; PMCID: PMC6918508.

Calcium and Dengue Virus

Q: Dengue virus infection causes? - select one

A) hypercalcemia

B) hypocalcemia 

Answer: B

Most of the treatment for the Dengue virus during all three phases of the Dengue virus, i.e., early, critical, and recovery phase, is essentially supportive. One of the unique features of the Dengue virus is hypocalcemia, and its cause is still not well understood. That said, it is significant, as the level of hypocalcemia correlates with the severity of illness. Its clinical significance can be understood from the perspective that, in resource-limited countries where the dengue virus is common, and labs may not be readily available, calcium should be replaced empirically, correlating clinically with the level of shock.

Development of seizures or arrhythmia due to hypocalcemia predicts poor outcome and requires constant monitoring and replacement, particularly in the critical phase. IV calcium gluconate is preferred. Replacement of calcium also helps restore the coagulation defects, a cardinal feature of Dengue virus infection.

#ID

References;

1. Pourzangiabadi M, Najafi H, Fallah A, Goudarzi A, Pouladi I. Dengue virus: Etiology, epidemiology, pathobiology, and developments in diagnosis and control - A comprehensive review. Infect Genet Evol. 2025 Jan;127:105710. doi: 10.1016/j.meegid.2024.105710. Epub 2024 Dec 26. PMID: 39732271.

2. Shivanthan MC, Rajapakse S. Dengue and calcium. Int J Crit Illn Inj Sci 2014; 4:314.

3. Constantine GR, Rajapakse S, Ranasinghe P, et al. Hypocalcemia is associated with disease severity in patients with dengue. J Infect Dev Ctries 2014; 8:1205.