Syndrome of Inappropriate Secretion of Antidiuretic Hormone Associated with H1N1 Infection

The syndrome of inappropriate secretion of antidiuretic hormone (SIADH) is related to several conditions. However, there are few reports associated with H1N1 virus infection. We describe a 36 year old patient with SIADH admitted to our department if internal medicine with fever, cough and myalgias. The labooratory analysis showed serum hypo-osmolar hyponatremia and high level of urinary sodium concentration. All other biological analysis were within normal range. Moreover, All bacterial and fungal cultures, blood and urine cultures were all negative for any microbial pathogen. The thoraco-abdominal CT scan was normal. Rapid flu test was positive for influenza type A 15 days after. The patient recovered with intravenous infusion of hypertonic saline and fluid restriction and he did not received any anti-viral drug. Despite a strong relationship betwwen H1N1 virus infection and   SIADH needs to be established, physicians should be aware of this potential seroius effect and should monitor the serum sodium closely. Keywords : H1N1 infection, inappropriate secretion of antidiuretic hormone, hyponatremia