The risk of TDF-induced nephrotoxicity with isolated hypophosphataemia, proximal tubular dysfunction or Fanconi syndrome increases in the presence of renal impairment.38 This is of particular concern in patients with comorbid HIV and DM, advancing age, lower CD4 cell counts and elevated baseline creatinine levels.38 Our study did not find TDF to be significantly associated with hypophosphataemia or serum phosphate levels in PLWH/DM. The gene discussed is CD4; the disease is Fanconi renotubular syndrome.