Thyroxine, triiodothyronine and thyrotrophin levels in meningococcal meningitis, typhoid fever and other febrile conditions.

Thyroid status was estimated serially by measuring triiodothyronine (T3), thyroxine (T4) and thyrotrophin (hTSH) in 20 patients suffering from meningococcal meningitis, typhoid fever and other acute febrile illnesses. Significantly low T3 and only slightly increased T4 were observed in all the patients. hTSH was normal in all of these. A significant reciprocal relationship was found between the degree of fever and fall in T3 concentrations. T3 tended to rise in patients who recovered but in those who deteriorated or died, T3 remained persistently low.