Challenges of Diagnosing Hyponatremic Syndromes in Pulmonary and Extra Pulmonary Tuberculosis

Introduction Pulmonary tuberculosis (PTB) is one of the rare pulmonary infections causing hyponatremia (serum sodium < 135 mmol/L) and severe hyponatremia (serum sodium < 125 mmol/L). Although the major cause of hyponatremia in TB patients is syndrome of inappropriate antidiuretic hormone (SIADH) secretion, cerebral salt wasting syndrome (CSWS) can occur and requires evidence of inappropriate urinary salt losses and reduced arterial blood volume. Adrenal insufficiency (AI) is rare in TB with scanty literature describing it. The two reported cases highlight three possible causes of severe symptomatic hyponatremia in TB pleural effusion and disseminated TB, their treatment modalities, and the need to increase the index of suspicion to diagnose TB hyponatremia in children. Case Report Case 1: a 10-year-old girl with TB pleural effusion who developed recurrent hyponatremia in the first few weeks of anti-TB treatment which was responsive to sodium correction. Case 2: an 8-year-old girl presenting to our facility with presumptive TB. She deteriorated over several months and progressed to disseminated TB with AI. Discussion Early diagnosis and prompt and correct treatment of TB hyponatremia cannot be overemphasized, as AI, SIADH secretion, and CSWS, each require different therapeutic regimens, most especially AI on its own poses a huge clinical challenge. Conclusion A high index of suspicion, with intensified case finding at all levels of care, is necessary to identify and manage children with TB hyponatremia because early diagnosis and prompt treatment is lifesaving.