High mortality rates have been reported in the first 90 days of antiretroviral therapy in Zambia and other low-income countries. We report a case of acute hypophosphataemia and hypokalaemia in the first week of antiretroviral therapy in a patient with extreme AIDS wasting. Given its occurrence in an extremely wasted patient, it may be physiologically similar to refeeding syndrome but other causes could be relevant as well. Acute hypophosphataemia may contribute to early antiretroviral therapy associated mortality in low-income countries.
