RESUMEN
Pheochromocytoma and paraganglioma (PPGL) have been associated with low bone mineral density (BMD) due to excess sympathetic system stimulation. Our study revealed low BMD and TBS (trabecular bone score) in cases compared to matched controls. Plasma-free nor-metanephrine and hypertension duration found to be most consistent predictive factors. PURPOSE: Pheochromocytoma and paraganglioma (PPGL) have been associated with low bone mineral density (BMD) and increased fracture risks. Sympathetic nervous system stimulation has been shown to increase bone resorption and decrease bone formation via ß2 receptors. Chronic inflammation and increased cytokine production add to more bone loss. TBS (trabecular bone score) is an established surrogate marker for bone histomorphometry. BMD and TBS data in pheochromocytoma and PPGL are scarce. The aim was to assess the BMD and TBS in pheochromocytoma and PPGL and look for clinical and biochemical predictors. METHODS: This case-control study had sample size of 58 (29 cases and controls each). BMI-, age-, and sex-matched controls were taken for comparison. Both cases and controls had undergone DXA scan and BMD {Z-scores and bone mineral concentration (BMC) in g/cm2} and TBS were analyzed. Detailed clinical histories and relevant biochemistry values were noted. RESULTS: The mean age of our case population was 29.5 ± 9.4 years with a mean age of HTN onset at 26.86 ± 6.6 years. Lumbar spine BMC (0.86 ± 0.14 vs 0.96 ± 0.15; p = 0.036), femoral neck Z-score (- 1.23 ± 1.07 vs - 0.75 ± 0.97; p = 0.003), and whole body BMC (0.91 ± 0.14 vs 1.07 ± 0.11; p = 0.000) were significantly low in cases compared to controls. Similarly, TBS was significantly lower in cases compared to controls (1.306 ± 0.113 vs 1.376 ± 0.083; p = 0.001). CONCLUSION: This study establishes both low bone mass and poor bone quality in an Indian pheochromocytoma and PPGL patient's cohort. Plasma-free nor-metanephrine and duration of hypertension were found to be most consistent predictive factors in multivariate regression analysis.
RESUMEN
A man in his 20s who had previously experienced multiple episodes of transient loss of consciousness, majorly attributable to the seizures, presented with a 1-month history of increased seizure frequency, high-grade fever and weight loss. Clinically, he had postural instability, bradykinesia and symmetrical cogwheel rigidity. His investigations revealed hypocalcaemia, hyperphosphataemia, inappropriately normal intact parathyroid hormone, metabolic alkalosis, normomagnesemic magnesium depletion, and increased plasma renin activity and serum aldosterone concentration. CT scan of the brain revealed symmetrical calcification of the basal ganglia. The patient had primary hypoparathyroidism (HP). A similar presentation of his brother indicated a genetic cause, most likely autosomal dominant hypocalcaemia with Bartter's syndrome type 5. The patient's fever was caused by underlying haemophagocytic lymphohistiocytosis secondary to pulmonary tuberculosis, which triggered acute episodes of hypocalcaemia. This case represents a complex interplay of a multifaceted relationship between primary HP, vitamin D deficiency and an acute stressor.