A 52-year-old Caucasian man with insidious onset dyspnoea, productive cough, lethargy, anorexia and weight loss presented to ED. On examination, he was febrile,dehydrated and cachectic. He was in hypoxic respiratory failure and required intubation. Chest X ray showed bilateral ground glass opacities which was confirmed on CT scan and Pneumocystis jirovecii infection was yielded from bronchoalveolar lavage. HIV infection was confirmed with viral load of 163000 viral copies/ml and initial CD4 count was 2uL (380-1390).
Marked hypercalcaemia was noted; corrected serum calcium was 3.22mmol/l (2.20-2.52). Initial iPTH was 1.7pmol/l (1.1-6.8) but subsequently iPTH was suppressed 0.3pmol/l as expected. The S.25OH Vit D was 96pmol/l and146pmol/l on 2 different occasions. His 1, 25 (OH) 2VitD was high 183 pmol/L (ranges 60 to 158).PTH-rP was normal. Fractional calcium excretion was >0.01.His ACE level, thyroid function and serum cortisol level was normal. Solid organ malignancy and haematological malignancies were excluded.Serology and cultures for viral, bacterial, fungal,mycobacterial and parasitic infections yielded negative results.
Patient was treated with Trimethoprim/Sulfomethoxazole and prednisone for 21 days for Pneumocystis pneumonia. Antiretroviral therapy (Truvada and Raltegravir) was commenced resulting in improvement in CD 4 counts and reduction in viral load. Hypercalaemia rapidly decreased with intravenous fluids. One month later calcium remained elevated 2.77mmol/l, 25(OH) Vit 108nmol/l and 1, 25 (OH) 2Vit D 160pmol/l.
In summary 51 yr old man who presented with Pneumocystis pneumonia and hypercalcaemia in the context of newly diagnosed HIV. There are many well recognised causes of hypercalcaemia in HIV, both endocrine and non-endocrine related. In our patient hypercalcaemia was initially attributed to Pneumocystis jirovecii infection. However hypercalcaemia did not resolve following adequate treatment which raises the possibility of other mechanisms in this patient.
This case highlights effects of HIV infection1; HIV related opportunistic infection2 as well as antiviral therapy on Vitamin D metabolism3,4.