Contralateral cranial polyneuropathy due to perineural invasion by a cutaneous squamous cell carcinoma.

Cutaneous malignancies may spread to underlying nerves, a process known as perineural invasion (PNI). We report a patient who was found to have PNI presenting as a cranial polyneuropathy on the contralateral side of the face many years after the resection of a squamous cell carcinoma. All diagnostic testing was unrevealing until nerve biopsy was performed. This emphasizes the long asymptomatic period between treatment of a cutaneous malignancy and detection of PNI, and the development of PNI at a site distant from the original malignancy. Biopsy of a clinically involved nerve may permit diagnosis of PNI when other studies are normal.

Unilateral congenital facial nerve paralysis secondary to a benign epithelioid peripheral nerve sheath tumor.

OBJECTIVE: A benign epithelioid peripheral nerve sheath tumor is described in the setting of congenital facial nerve (FN) paralysis. This is the first reported case in the English literature. PATIENT: A 10-month-old girl with unilateral congenital FN paralysis. INTERVENTIONS: Auditory brainstem evoked potential study, gadolinium-enhanced magnetic resonance imaging, temporal bone computed tomography, and transmastoid FN decompression with tumor resection. MAIN OUTCOME MEASURES: Follow-up for tumor recurrence and postoperative FN function. RESULTS: The child underwent a transmastoid FN exploration with resection of a 0.6-cm spherical tumor analyzed to be a benign epithelioid peripheral nerve sheath tumor. There is no evidence of recurrence, and FN function was unchanged at 1 year postoperatively. CONCLUSION: Benign epithelioid peripheral nerve sheath tumor can cause congenital facial nerve palsy.

Comparative immunohistochemical assessment of craniopharyngioma and related lesions.

Craniopharyngiomas (CP), Rathke's cleft cysts (RCC), and sellar xanthogranulomas (XG) are closely related lesions. As expression of cytokeratins 8 (CK8) and 20 (CK20) was reported in RCC but not in CP, the present study investigates the reproducibility of immunohistochemical distinction between CP and RCC, attempting to identify the relationship of XG to these lesions. A comparative study of 55 patient specimens (25 CP, 28 RCC, and 2 XG) was analyzed for the histological features of xanthomatous changes and squamous metaplasia, and expression of CK8 and CK20. In the 25 CP cases, xanthomatous changes were seen in 5 (20%), with CK8 reactivity demonstrated in all 25 cases. A prominent xanthomatous component was identified in 13 of 28 RCC (46%), and squamous metaplasia was seen in 11 (39%), 9 of which also contained xanthomatous features. CK8 reactivity was demonstrated in all 28 RCC cases, whereas CK20 was seen only in 9 cases (32%). Of the two cases diagnosed as XG, none contained epithelium, and immunohistochemistry for cytokeratins was not observed. Overall, differential expression of cytokeratins cannot reliably distinguish CP from RCC. Furthermore, expression of CK20 in RCC is generally seen within a background of prominent squamous metaplasia and reactive xanthomatous changes.

Schwannomatosis in a patient with a pelvic mass: case report.

Schwannomatosis is the most recently recognized form of neurofibromatosis in which patients harbor multiple non-vestibular nerve schwannomas. The diagnosis is contingent on excluding neurofibromatosis Type 2 (NF2), to which it is related. The authors present a case of schwannomatosis diagnosed fortuitously when a preoperative magnetic resonance (MR) image of a pelvic schwannoma was suggestive of a lesion in the lower lumbar canal. Definitive studies confirmed the presence of multiple spinal tumors including a thoracic schwannoma, which was removed during a subsequent procedure. This case emphasizes the need to consider the possibility of multiple tumors in every patient presenting with a schwannoma because the follow-up and genetic counseling are vastly different in those with NF2 and schwannomatosis compared with those harboring sporadic tumors. Details of this case and current considerations in the diagnosis and management of schwannomatosis are discussed.

A case of hereditary inclusion body myopathy: 1 patient, 2 novel mutations.

Hereditary inclusion body myopathy is an autosomal recessive disorder that presents in early adulthood with slowly progressive weakness sparing the quadriceps. Muscle histopathology reveals rimmed vacuoles without inflammation. The disorder is caused by a mutation in the gene for UDP-N-acetylglucosamine 2-epimerase-N-acetylmannosamine kinase (GNE), a bifunctional enzyme involved in protein glycosylation. Over 40 mutations have been described to date. We present a case of a young woman with progressive lower extremity weakness. Clinical presentation, laboratory evaluation, electrodiagnostic testing, muscle pathology, and genetic sequencing are described. The patient was found to have heterozygous mutations in the GNE gene, confirming the diagnosis of hereditary inclusion body myopathy. The mutations she carried have not been described previously. We briefly review the clinical, histopathologic, and molecular genetic findings of this disorder.

Mononeuritis multiplex secondary to sarcoidosis.

Peripheral nerve involvement is a rare, yet treatable neurological manifestation of sarcoidosis. Most patients respond well to corticosteroids, but relapses are common and the long-term prognosis remains unpredictable. We present a patient with an asymmetrical neurological presentation of previously undiagnosed sarcoidosis. She presented with paresthesias and predominantly distal extremity weakness. Other possible causes of neuropathy were ruled out and she was found to have an elevated serum ACE level. A nerve/lip biopsy demonstrated non-caseating granulomas consistent with sarcoid. Her clinical outcome was favorable after initiating treatment with high dose oral prednisone.

Secondary energy failure after cerebral hypoxia-ischemia in the immature rat.

A delayed or secondary energy failure occurs during recovery from perinatal cerebral hypoxia-ischemia. The question remains as to whether the energy failure causes or accentuates the ultimate brain damage or is a consequence of cell death. To resolve the issue, 7-day postnatal rats underwent unilateral common carotid artery occlusion followed thereafter by systemic hypoxia with 8% oxygen for 2.5 hours. During recovery, the brains were quick frozen and individually processed for histology and the measurements of 1) high-energy phosphate reserves and 2) neuronal (MAP-2, SNAP-25) and glial (GFAP) proteins. Phosphocreatine (PCr) and ATP, initially depleted during hypoxia-ischemia, were partially restored during the first 18 hours of recovery, with secondary depletions at 24 and 48 hours. During the initial recovery phase (6 to 18 hours), there was a significant correlation between PCr and the histology score (0 to 3), but not for ATP. During the late recovery phase, there was a highly significant correlation between all measured metabolites and the damage score. Significant correlation also exhibited between the neuronal protein markers, MAP-2 and SNAP-25, and PCr as well as the sum of PCr and Cr at both phases of recovery. No correlation existed between the high-energy reserves and the glial protein marker, GFAP. The close correspondence of PCr to histologic brain damage and the loss of MAP-2 and SNAP-25 during both the early and late recovery intervals suggest evolving cellular destruction as the primary event, which precedes and leads to the secondary energy failure.

Neuropathology of seizures in the immature rabbit.

Acute morphologic changes of brain due to chemically induced seizures are studied in developing rabbits. Accordingly, rabbits of postnatal days 6 and 7 (p6-7) and p10-12 are injected with a single dose of 1-6 mg/kg kainic acid (KA) intraperitoneally (i.p.) or injected with a single dose of 200-300 mg/kg pilocarpine subcutaneously (s.c.). Many animals developed seizures of varying severity and length. Histologic examination of brain 2 days following injection showed that KA-induced seizures did not cause neuronal death. Pilocarpine-induced seizures resulted in neuronal death mainly involving the CA1 region of hippocampus. In the p6-7 group, only a small number of brains were involved, lesions were mild and limited to CA1. In the p10-12 group, majority of the brains were damaged, lesions were relatively severe, and in some brains extended beyond the CA1 region involving the subiculum, CA3, cortex, and amygdala. Measurements of physiologic parameters indicate that these changes were not secondary to hypoxemia during seizures. However, there was hypotension and hyperthermia, both of which may contribute to brain damage during seizures. The findings suggest that pilocarpine-induced seizures during the second postnatal week in rabbits is a useful model to study the morphologic changes of brain due to seizure in the developing animal and also to assess the systemic physiologic alterations during seizures.

A histological and anatomical profile of pacinian corpuscles from Dupuytren's contracture and the expression of nerve growth factor receptor.

The etiology of Dupuytren's disease is unknown. The causes of the fibroplastic response of nodules, fibrosis of cords, and prominence of pacinian corpuscles are not evident. Histological and immunohistology differences in pacinian corpuscles from the hands of five patients with Dupuytren's disease compared with 17 Dupuytren's-free patients are presented. Histological sections of pacinian corpuscle specimens were stained with hematoxylin and eosin and immunostained for nerve growth factor receptor. The length and width of intact pacinian corpuscles were measured, and the number of layers within each corpuscle was counted and recorded. Grossly, the pacinian corpuscles from Dupuytren's patients were larger and more numerous compared with those from unaffected patients. When measured microscopically, the pacinian corpuscles from Dupuytren's diseased fascia were significantly larger (2.0 x 1.1 mm) compared with controls (1.5 x 0.78 mm). The pacinian corpuscles from Dupuytren's-affected patients had significantly more layers (64 +/- 14) compared with those from control patients (40 +/- 9). Nerve growth factor receptor staining of pacinian corpuscles from patients affected with Dupuytren's disease showed greater intensity and more area stained compared with unaffected controls. It is suggested that nerve growth factor may be involved in the increased size of pacinian corpuscles in Dupuytren's-affected fascia. It is proposed that the cellular outgrowth from pacinian corpuscles may generate the cells that develop into Dupuytren's nodules.

Muscle biopsy in the evaluation of patients with modestly elevated creatine kinase levels.

The utility of muscle biopsy in patients with modest elevations of serum creatine kinase (CK) level but normal neurological examinations and nondiagnostic electrodiagnostic studies is uncertain. We performed systematic, extensive studies on muscle biopsies of 20 such patients. A definitive diagnosis was arrived at in only 1 by histochemical studies, although 4 others demonstrated minor myopathic changes. Biochemical evaluation led to a diagnosis in an additional 5. Muscle biopsy is useful for evaluating such patients, but extensive studies of the muscle are necessary.

Sporadic inclusion body myositis and hereditary inclusion body myopathy.

Sporadic inclusion body myositis (s-IBM) is a common but under-recognized myopathy in individuals over 50 years of age. An awareness of the clinical phenotype and of the electrodiagnostic and histopathologic features should lead to improved recognition, and should minimize confusion with polymyositis, motor neuron disease, and other neuromuscular disorders. Treatment efficacy has been difficult to judge because of the insidious progression of the disease over many years, but immunomodulating therapy is generally less effective than in polymyositis and dermatomyositis, and may not be effective at all in many patients. The hereditary inclusion body myopathies (h-IBM) are a heterogeneous group of recessively and dominantly inherited vacuolar myopathies that share some histologic features with s-IBM. Oxidative stress may play a role in the pathogenesis of both s-IBM and h-IBM.