A rare case of polymyositis

The human T-lymphotropic virus type 1 (HTLV-1) is a retrovirus that infects 10 to 20 million people worldwide and although the majority of HTLV-1 infected individuals will remain asymptomatic, there are two well-recognized disease associations caused by the virus:1) Adult Tcell leukemia-lymphoma (ATL) 2) HTLV-1 associated myopathy (HAM)Case presentation:Our patient is a 43 year-old man who first presented with symptoms associated with proximal upper and lower limb muscle weakness, including: difficulty in climbing upstairs and raising arms above his head. Through physical examination a severe decrease in proximal muscle forces (both upper and lower extrimities), without deep tendon reflex or sensory involvement, was detected. A thorough laboratory test was indicative of an elevation in liver enzymes (AST,ALT), muscle-related enzymes and a positive serological test for HTLV-1. Later on, he did an EMG-NCV test which showed an inflammatory pattern. To confirm the diagnosis he under went musle biopsy that proved polymyositis. On follow up, according to positive serological HTLV-1 and in order to authenticate the diagnosis of HAM , he got a Lumbar puncture and HTLV-1 Ab was found in CSF.Discussion and conclusion:HTLV-1 associated myopathy (HAM) affects less than 2% of HTLV-1 carriers with higher prevalence in females. Among different types of myopathiese, polymyositis is considered to be a rare manifestation of HTLV-1 infection.

Keywords:

HTLV-1 associated myopathy , HAM , human T-lymphotropic virus type 1 , HTLV-1 , polymyositis