A preliminary study on electromyographic analysis of the paraspinal musculature in idiopathic scoliosis

The paraspinal muscles have been implicated as a major causative factor in the progression of idiopathic scoliosis. Therefore, the objectives of this preliminary study were to measure the electromyographic activity (EMG) of the paraspinal muscles to determine its relationship to progression of the scoliotic curve. Idiopathic scoliotic patients were selected and identified afterwards on curve progression. The EMG activity on both sides of the spine was measured in a set of standardized postures using bipolar surface electrodes at the apex and two end vertebrae of the scoliotic curve. An EMG ratio involving measurements of the EMG activity on the convex and concave sides of the scoliotic curve was used to evaluate the paraspinal muscles. Enhanced EMG ratios at the apex of the scoliotic curve were found in both groups during sitting and standing. The most interesting finding was that children with progression of the curve also showed enhanced EMG ratios at the lower end vertebra of the curve. The EMG ratios between the groups were significantly different from each other at the apex and end vertebrae for several test conditions. Overlap in the EMG-ratio ranges made differentiation difficult for prediction of the progression of the individual scoliosis patient. However, the EMG ratio at the lower end vertebra of the scoliotic curve is significantly higher than 1 in all test conditions in the group of children with subsequent progression of the curve, whereas it is always normal in the non-progressive group. Therefore, EMG of the paraspinal muscles might be of value for prediction of progression in idiopathic scoliosis.     

Histologic features of paraneoplastic pemphigus.

BACKGROUND--We describe the histopathologic features of paraneoplastic pemphigus, a recently described autoimmune mucocutaneous disease associated with neoplasia. Complete evaluation for paraneoplastic pemphigus requires identification of the characteristic mucocutaneous eruption, tissue specimens for routine histologic and direct immunofluorescence evaluation, and identification of circulating autoantibodies with a unique specificity. Immunoprecipitation from keratinocytes reveals a characteristic complex of four proteins with the circulating antibodies. Various neoplasms have been identified in patients with paraneoplastic pemphigus. OBSERVATIONS--We reviewed 16 skin and oral mucous membrane biopsy specimens from six patients with paraneoplastic pemphigus confirmed by fulfillment of all criteria. Major features include epidermal acantholysis, suprabasal cleft formation, dyskeratotic keratinocytes, vacuolar change of the basilar epidermis, and epidermal exocytosis of inflammatory cells. Seven (44%) of 16 specimens displayed a unique combination of suprabasal acantholysis and dyskeratotic keratinocytes throughout the epidermis. These histologic findings correspond to those of the characteristic clinical lesions that are described as having features of pemphigus and erythema multiforme. CONCLUSIONS--Paraneoplastic pemphigus represents a unique clinical, histologic, and immunologic disease characterized by autoantibody production to desmoplakin I and desmoplakin II, bullous pemphigoid antigen, and, possibly, other antigens in the desmosomal complex. Recognition of the histologic features should prompt immunopathologic confirmation and evaluation for an occult neoplasm.     

Can active lateral canal benign paroxysmal positional vertigo mimic a false-positive head thrust test?

We present a patient with positive head thrust test (HTT) and video-oculography (VOG) findings suggestive of active lateral semicircular canal (LSCC) benign paroxysmal positional vertigo (BPPV). This patient was seen in a tertiary vestibular clinic for episodic vertigo. He exhibited robust corrective refixation saccades on HTT to the right and evidence of active contralateral LSCC BPPV on positional testing. Treatment of the LSCC BPPV led to immediate resolution of vertigo and near-normalization of the HTT on follow-up testing. The pathophysiologic basis and clinical implications of LSCC BPPV mimicking a false-positive HTT are discussed in detail.     

Cutaneous graft-versus-host reaction lacks evidence of cutaneous cytomegalovirus by the immunoperoxidase technique

Sixty skin biopsy specimens from 21 bone-marrow transplant patients were evaluated for the presence of cytomegalovirus (CMV) using two monoclonal antibodies to early and late antigens. Each patient had at least one biopsy showing an acute graft-versus-host reaction (GVHR), grade 2, and one positive culture for CMV from blood, bone marrow or urine. In no case could CMV antigens be identified in biopsies showing an acute or chronic cutaneous GVHR or in any other of the skin biopsies obtained from these patients. While CMV may play a role in immunologic events culminating in graft-versus-host disease (GVHD), this immunoperoxidase study did not reveal evidence of viral antigens in tissue displaying features of cutaneous GVHR.     

Elastosis perforans serpiginosa-like pseudoxanthoma elasticum in a child with severe Moya Moya disease

A 2-year-old girl with Moya Moya disease who had relapsing cerebrovascular strokes presented with loose skin folds, 'chicken' skin appearance and perforating elastosis serpiginosa-like lesions in the genitocrural region. Histologically, calcified material perforating the epidermis and adjacent short curled and mineralized elastic fibres suggested a variant of pseudoxanthoma elasticum (PXE). As PXE is known to be caused by various mutations in the transmembrane transporter ABCC6 gene, we hypothesized that a novel ABCC6 mutation may underlie this unique combination of PXE and elastopathic vascular damage. Therefore, the complete ABCC6 coding region of the patient and her parents was screened for genetic alterations. No bona fide disease-causing mutation of ABCC6 could be found in the child and in her parents. However, two novel allelic amino acid substitutions (Arg1273Lys and Glu1293Lys; exon 27) were found in the girl and her father, localized in close proximity to the region that codes for the functionally critical second nucleotide-binding fold of ABCC6. Although a causal involvement of these amino acid substitutions could not be proven based on this study, both heterozygote substitutions may possibly have interacted with other undetected recessive maternal ABCC6 changes in the child. To the best of our knowledge, this is the first report of an association between early-onset PXE and severe Moya Moya syndrome possibly related to ABCC6 changes.     

Interleukin 2 and granulocyte-macrophage colony-stimulating factor induce a perivascular lymphocytic infiltrate in a skin explant model.

Cutaneous eruptions displaying perivascular inflammatory cell infiltrates histologically may develop with the intravenous administration of cytokines. Similar findings are seen spontaneously in some patients on recovery of peripheral blood lymphocytes after profound marrow aplasia. To investigate the production of a cutaneous perivascular infiltrate further, the ability of several cytokines to induce a perivascular lymphocytic infiltrate was studied in vitro using a skin explant model. A skin biopsy specimen obtained at the time of peripheral blood lymphocyte recovery after chemotherapy-induced marrow aplasia (n = 10) was divided and incubated for 3 days with and without a series of cytokines plus various peripheral blood mononuclear cell populations. Skin incubated with interleukin 2 and granulocyte-macrophage colony-stimulating factor induced a perivascular lymphocytic infiltrate, while control samples did not. Immunophenotypic analysis revealed that the lymphocytes were predominantly CD3+/CD4+. An infiltrate was not observed when skin was incubated with cytokines alone, without the addition of simultaneously isolated peripheral lymphocytes. A perivascular pattern was not observed with the addition of interferon gamma. Only interferon gamma induced keratinocyte intercellular adhesion molecule 1 expression in experimental tissue. Certain cytokines that affect a range of cell types are capable of inducing a common cutaneous histologic pattern, the perivascular lymphocytic infiltrate.     

Recent observations on the serology of syphilis.

Routine screening of 404 742 sera by the automated micro-haemagglutination assay (AMHA-TP) and the Venereal Disease Research Laboratory (VDRL) test showed that 9848 specimens gave a reactive result to one of the three assays. Reactive results were confirmed by the fluorescent treponemal antibody absorption (FTA-ABS) test. The possibility of false-positive results varied from 0.04-0.38% of all specimens or from 1.7-15.7% of reactive sera. The VDRL test failed to detect reactivity in 56.54% of sera from patients who had previously been infected with Treponema pallidum. The importance of routine testing by the AMHA-TP is illustrated by the detection of four patients with mesaortitis and two with active neurosyphilis among a selected group of 54 patients who had non-reactive results to the VDRL test. Testing of cerebrospinal fluid specimens by the AMHA-TP test produced more specific results than by the other two tests.     

Paternal effects on offspring fitness in a multimale primate society

When females mate with multiple males, paternal care is generally expected to be negligible, because it may be difficult or impossible for males to discriminate their own offspring from those of other males, and because engaging in paternal care may reduce male mating opportunities. Consequently, males in multimale societies are not predicted to provide direct benefits to their offspring. We have recently demonstrated, however, that males in a typical multimale primate society (yellow baboons, Papio cynocephalus) discriminate their own offspring from those of other males and provide care to them in the form of repeated support during agonistic encounters. This observation raises the question of whether fathers enhance offspring fitness in this species. Here we use 30 years of data on age at maturity for 118 yellow baboons with known fathers. We show that the father's presence in the offspring's social group during the offspring's immature period accelerated the timing of physiological maturation in daughters. Sons also experienced accelerated maturation if their father was present during their immature period, but only if the father was high ranking at the time of their birth. Because age at reproductive maturity has a large impact on lifetime reproductive success, our results indicate a direct effect of paternal presence on offspring fitness. This relationship in turn suggests that the multiple roles that males play in multimale animal societies have not been sufficiently examined or appreciated and that paternal effects may be more pervasive than previously appreciated.