Dengue Fever: Transient Variable AV Conduction Block (2:1 with Mobitz Type I Second Degree) During Recovery Phase

We report a case with serologically (MAC ELISA) proven acute dengue virus infection and variable atrio-ventricular (AV) conduction block (2:1 with Mobitz type I second degree). A 23 years old boy was referred to the hospital on the 7th day of the illness for thrombocytopenia (19000/cmm) with fever and body aches. On day 11th of the illness, during recovery phase he developed variable AV conduction block. There was no other abnormality in the 12-lead electrocardiogram (ECG) except occasional VPCs and echocardiogram showed normal ventricular systolic function. CPK-MB, serum electrolytes were normal. Trop-T was negative. The pulse and rhythm resolved to normal on day 13th. AV block during recovery from dengue fever may be a transient functional phenomenon, in which altered autonomic tone may play a role and conservative but vigilant management may be justified.