Mycobacterium leprae (Leprosy)

Relapsed leprosy
Relapses often occur more than 5 years after suspected cure, which makes them difficult to diagnose. In one series of 12 patients, average time between end of prior treatment and diagnosis was 11 years. They present with new neuropathic findings without evidence of new cutaneous lesions. Usual signs/symptoms include: Diagnosis is difficult. Only 33% of patients in one series had a positive anti-PGL1 IgM serology. M. leprae DNA PCR in serum was only positive in 8%, and on slit-skin smears was positive in 50%.
 * Hypesthesia, paresthesia, and/or pain: 92%
 * Nerve thickening: 83%
 * Muscle weakness and/or amyotrophy: 66%
 * Visible deformities: 33%