Acute Hepatitis B Associated Neuromyopathy
A 67 year old man presented with abdominal discomfort and jaundice for 1 month with difficulty in walking with severe pain in both thighs of 3 days duration. He was a diabetic and hypertensive on medications. There was no history of HMG CoA reductase inhibitor use. On examination he had icterus and grade 2 power in the proximal upper and lower limbs. Deep tendon reflexes were inelicitable. On day 1, CRP was 37mg/L and liver function tests were deranged [ Total Bilirubin 16 mg%, direct 14.3mg%,
... GOT [920 U/L], SGPT [590 U/L], Alkaline Phosphatase 276.5 U/L. Serum CPK levels [9768 U/L], LDH [979 U/L] and Ferritin [7264 ng/ml] were elevated on day 2. ANA profile was negative. Leptospiral antibody, dengue serology and SARS-CoV2 RT-PCR were negative. Hepatitis B serology was compatible with an acute infection. On day 3, nerve conduction studies showed an axonal sensory-motor polyneuropathy predominantly involving the lower limbs. F waves were absent. Fibrillations and positive waves were picked up from the Tibialis anterior muscles bilaterally. He was started on IVIG 2gm/kg x 5 days. On day 4, his CPK levels increased to >42,000 U/L and he was shifted to the ICU and started on forced alkaline diuresis. Urine myoglobin was positive.. On day 6, MRI whole body muscle STIR imaging showed patchy ill-defined STIR hyperintensities involving the muscles of the gluteal, pelvic girdle muscles, both thighs and leg muscles with fascial edema. The muscles of the upper limbs and shoulder girdles also showed patchy STIR hyperintensities. Diffuse subcutaneous oedema was noted in the soft tissue of the thighs, legs and abdominal wall. Over the next few days, the weakness in the upper limbs worsened and he developed a weak cough. He did not consent to a lumbar puncture or muscle biopsy. Over the next 9 days, his liver function tests and CPK levels gradually normalised. He was also started on Entacavir. By day 10, his upper limb and distal lower limb had improved to grade 4/5 power and he was able to stand with support and he was discharged.