A 40-year-old male with loss of consciousness was referred to neurology ward (AL-Zahra Hospital) after controlling for the elevation of creatine phosphokinase (CPK) (4050 U/L) and creatine (Cr) levels (4.9 mg/dL) due to rhabdomyolysis and acute renal failure in nephrology department. Hemodialysis approach was performed for him. In neurology service, he complained paresthesia in the upper limb, myalgia, cramp, and weakness in the lower limb without fasciculation. He worked in a battery manufacturing company and had no past medical and drug history or drug abuser.
On physical examination, tenderness and swelling in the right limb were detected. Given neurologic examination, the patient could not walk without aid, and generalized atrophy was seen without fasciculation. Force of muscle in upper limb both in proximal and distal was 5/5, in lower limb of the proximal part in the right side 1/5 and in left side 3/5, and in distal part was 0/5. Deep tendon reflex (DTR) was +2 in upper limb, +1 in left knee, 0 in left Achilles, and 0 in right knee and Achilles. Babinski was negative; stock sensory loss, abnormal position, and vibration sense in lower limb were detected.
Laboratory data showed CPK (1315 unit/L), lactate dehydrogenase (LDH) (1550 unit/L), increased levels of liver enzymes (aspartate aminotransferase: 75 unit/L, alanine aminotransferase; 88 unit/L), gamma-glutamyl transferase level (152 unit/L and minimally elevated blood urea nitrogen (41 mg/dL), Cr (1.8 mg/dL), and thyroid-stimulating hormone (21.4 mu/l). Vasculitis test and ganglioside antibodies panel, cerebrospinal fluid (CSF) analysis, Brucella antibodies, hepatitis B surface antigen, hepatitis C virus Ab, and HIV Ab were all normal. Moreover, the urine toxin screen test for morphine was positive (only one time) and in second and third time was negative. BLL (6 months before this symptom) was 75 mug/dL, and it was rechecked again after hemodialysis in hospital, and the BLL in three separate times was 30, 10, and 12 mug/dL. In addition, mild polychromasia, hypochrome, and anisocytosis in blood smear were reported. CBC analysis showed that elevated level of leukocytosis (white blood cell: 15,800/mm3 and anemia (red blood cell: 3.50Mil/mm3, Hb: 10.6 g/dL, Hct32.6%) was reported.
Electrophysiological test revealed a severe acute-subacute polyradiculoneuropathy with nonirritative proximal myopathy in lower limbs, without any evidence of compression neuropathy pattern. Magnetic resonance imaging (MRI) showed hyperintensity in the anterior and posterior compartment in both thighs (right > left) and also in paraspinal muscles in short-tau inversion recovery [Figure 1]. Thereafter, magnetic resonance neurography (MRN) was ordered, which showed multilobulated collection in the right gluteus muscle and right femur neck osteomyelitis; however, lumbosacral nerve roots were normal [Figure 2]. Normal Doppler sonography of limb and abdomen and pelvic sonography for rule out of deep venous thrombosis were performed which no evidence was found.
First, with suspicious of autoimmune neuropathy, treatment was started with intravenous immunoglobulin (IVIG), but due to lack of efficacy and having allergy to drug, it was stopped. After, the first evaluation, with suspicious of nondiabetic polyradiculoneuropathy, the patient was treated with corticosteroids and due to MRN findings was referred to infectious service. After taking antibiotics without efficacy, corticosteroid regimen was stopped, and the patient was discharged.
Three months later, he was admitted again in our neurology ward. On neurological examination, he was wheelchair-bound, like before generalized atrophy was seen but without fasciculation. Force of muscles decreased as 3 months ago, and DTR was absent in both upper and lower limbs. Again, vasculitis test and CSF analysis were normal. The normal level of myositis-specific antibodies panel was measured. Erythrocyte sedimentation rate, C-reactive protein, and tuberculosis antibodies were normal. Hemoglobin levels were measured 12, 11, 10.3, and 9.7 g/dL in different times.
In new electromyography finding, a severe subacute lumbosacral polyradiculoneuropathy with proximal myopathy in the lower limb and paraspinal muscle was reported. Plasma exchanged was started without efficacy. In second lumbosacral MRI with Gadolinium enhancement of paraspinal muscles was reported [Figure 3]. In MRI of hip and thigh, hyperintensity in proximal muscles, particularly in the right side with avascular necrosis in the right femur neck, was noticed [Figure 4]. In addition, hyperintensity in anterior and posterior muscles in leg MRI was presented [Figure 5]. With these results, it was decided to take the patient to muscle biopsy, confirming the diagnosis. In muscle biopsy, severe necrosis was displayed, and in left sural nerve biopsy, a mild wall thickening in vessels without infiltration with no evidence of vasculitis was shown [Figure 6].
All paraclinical tests for acute polyradiculoneuropathy such as ganglioside antibodies panel, CSF analysis, and vasculitis test and also for necrotizing myopathy such as myositis-specific antibodies panel were performed, and we did not find any etiology except increased BLL (30 mug/dl). In retrograde examination, blue line in gum of the teeth was detected [Figure 7], and the patient was referred to poisoning specialist, and penicillamine (500 mg q8h) with pyridoxine (50 mg daily) for 8 months was started for him. Penicillamine is the only accessible drug for lead intoxication in Iran. After treatment, the BLL reached to 20 mug/d. In follow-up examination, the force of muscles in the proximal part of the lower limb was mildly improved (+3/5 in both sides), but the force of distal muscles was not improved (0/5). Finally, the patient was advised to monthly follow-up of BLL and neurologic exams.