A Diagnostic Pitfall: Hidden Hazards of Lead Neuropathy by Co-Existence of Hemoglobinopathy and Cervical Radiculomyelopathy.

A 52-year-old Myanmar man presented with bilateral progressive painless asymmetrical wrist and finger drop in 1 year without any sensory and sphincter problems. He has hypochromic microcytic anemia diagnosed as Hemoglobin E disease before. However, a serial full blood count revealed thrombocytopenia and a drop in hemoglobin disproportionate to HbE disease. Neurophysiology testing indicated axonal motor polyneuropathy affecting the distal C7 and C8 muscles. His MRI showed spinal cord myelopathy and neural foraminal narrowing at C5-C6 and C6-C7, but MRI findings could not explain both his C8 weakness and electromyography findings of C8 radiculopathy. However, he was initially managed as Hemoglobin E disease and spondylotic cervical radiculomyelopathy. The patient has been operating a car workshop for over a decade, without any apparent history of direct exposure to lead-contaminated batteries or lead-based paint. However, due to suspicion of lead exposure raised by his family doctor, blood lead level testing was initiated. A more detailed occupational history revealed that the patient collected discarded air-conditioning units in his workshop for recycling purposes and stored them in poorly ventilated spaces. Handling these items likely exposed him to a significant amount of lead dust and fumes. Finally, he was diagnosed with lead neuropathy, and after appropriate treatment, his muscle strength and blood counts returned to normal.