Severe hyperkalemia and muscle weakness in HIV-associated Pneumocystis jirovecii pneumonia treated with high-dose trimethoprim-sulfamethoxazole and corticosteroids: A case report.

BACKGROUND

High-dose trimethoprim-sulfamethoxazole (TMP-SMX) combined with corticosteroids is the first-line treatment for severe Pneumocystis jirovecii pneumonia (PJP) in HIV patients but carries a risk of severe hyperkalemia and muscle weakness.

CASE PRESENTATION: We report a 56-year-old male with advanced HIV (CD4: 14 cells/μL) and type 2 diabetes mellitus, treated for PJP with TMP-SMX 20 mg/kg/day and methylprednisolone 80 mg/day. On day 10 of treatment, the patient developed severe muscle weakness and life-threatening hyperkalemia (8.2 mmol/L) unresponsive to medical management, requiring emergency intermittent hemodialysis (IHD). After one hemodialysis session and switching to clindamycin-primaquine, potassium levels normalized within 2 days, and muscle weakness gradually improved and resolved after 4 days. The patient was discharged in a stable condition after 21 days of treatment.

CONCLUSION

This case represents a rare clinical complication with extremely severe hyperkalemia (8.2 mmol/L) accompanied by muscle weakness, likely due to the synergistic effect of hyperkalemia and steroid myopathy. Hemodialysis is an effective and safe intervention for hyperkalemia unresponsive to medical management. Close monitoring of electrolytes and muscle function is crucial in patients receiving high-dose TMP-SMX in combination with corticosteroids, particularly during the first 10 days of treatment.