Sleep deprivation in the rat: VI. Skin changes.

All rats subjected to total or paradoxical sleep deprivation by the disk apparatus developed severe ulcerative and hyperkeratotic skin lesions localized to the plantar surfaces of their paws and to their tails. Yoked control rats only occasionally developed similar appearing lesions, which were always much less severe than in deprived rats. The deprived rat lesions could not be explained by pressure, disk rotation, water immersion, infection, necrotizing vasculitis, tyrosinemia, protein deficiency, or reduced rates of mitosis. Thus, although paw and tail lesions constitute a very reliable and severe symptom of total or selective sleep deprivation in the rat that potentially could yield insights into the pathogenic mechanisms induced by sleep loss, the mediation of the lesions remains unknown.

An outbreak of Norwegian scabies in a surgical ward.

An outbreak of Norwegian scabies in a surgical ward of a teaching hospital was reported. The source of infestation was an elderly diabetic. The epidemic involved 28 of 32 medical personnel in the ward and 3 family contacts. All infected individuals were given a two-course treatment with hexachlorcyclohexane gel. Control of the outbreak was achieved by strict handwashing after patient contact, application of gowns and gloves for contact with skin lesions and the treatment of infected persons. Norwegian scabies in institutions is on the rise, vigilance for its occurrence is needed.

Clinical and microbiologic findings in cellulitis in Thai patients.

BACKGROUND: Cellulitis is an inflammation of subcutaneous tissue in which infective, generally bacterial cause is proven or assumed. However, attempts to culture bacteria from lesions are often unsuccessful. METHOD: One hundred and fifty cases diagnosed as cutaneous cellulitis at Siriraj Hospital between 1992 and 1995 were retrospectively studied. RESULTS: Our study in 150 adult Thai patients with cellulitis showed that the most common site of infection was the lower extremity. Forty two per cent of the patients had history of preceding local trauma. Fever and regional lymphadenopathy were detected in 77.3 per cent and 22.6 per cent respectively. Sixty nine per cent of patients had leukocytosis with a mean neutrophil ratio of 79.7 per cent of patients with underlying diseases predisposed to the infection, 61.6 per cent had positive lesional culture results in contrast to 31.6 per cent in patients without. Needle aspiration and blood gave low positive culture yields. The common organisms detected were S.aureus and Streptococcus group A (83%) in immunocompetent patients. Of immunocompromised patients, in one half of the cases gram negative bacteria were found. CONCLUSIONS: This study showed that in immunocompetent patients, the major bacterial isolated in cellulitis were S.aureus and Streptococcus group A. In immunocompromised patients, gram negative bacteria were found in one half. These findings may help in the selection of antimicrobials before the results of bacterial cultures are available or in culture negative cases.

Diagnostic value of IgM deposition at the dermo-epidermal junction.

BACKGROUND: Granular immunoglobulin M (IgM) deposits at the dermo-epidermal junction (DEJ) are common in lupus erythematosus (LE); however, weak, interrupted, linear and granular patterns of IgM at the DEJ have been reported in sun-exposed skin in normal adults and in a heterogeneous group of diseases. MATERIALS AND METHODS: We analyzed 200 patients with positive IgM direct tissue immunofluorescence deposition at the DEJ, alone or in combination with other immunoreactants, in order to determine the diagnostic significant of IgM deposition at the DEJ. RESULTS: IgM deposition at the DEJ, commonly in combination with other immunoreactants, was associated with LE in 57.5% of patients. In cases with IgM deposition alone at the DEJ, only 12% had LE (strong intensities). IgM deposition at the DEJ was associated with other dermatoses in 42.5% of patients. In non-lupus patients, IgM deposition was the sole finding in 59% of cases, and was weaker and more focal than in LE patients. CONCLUSIONS: IgM deposition at the DEJ in patients with LE tends to exhibit a strong intensity and is commonly detected in combination with other immunoreactants. IgM deposition alone at the DEJ, especially of weak intensity or focal in pattern, is noted in non-lupus patients, and has less diagnostic significance.

Panniculitis in tuberculosis: a clinicopathologic study of nodular panniculitis associated with tuberculosis.

BACKGROUND: Certain types of panniculitis, erythema induratum of Bazin and erythema nodosum, have been well documented as tuberculids. Many histopathologic diagnoses of panniculitis have been reported in tuberculosis patients. This study investigates the correlation between underlying tuberculosis and clinicopathologic findings of panniculitis. METHODS: We retrospectively reviewed the clinical files of histologic-proven panniculitis cases at the Dermatologic Clinic, Siriraj Hospital from January 1992 to December 1995; only cases with active tuberculous foci were analyzed. RESULTS: The incidence of panniculitis caused by tuberculosis was 8.2%. The ratio of men to women was 1:1. The mean age of onset was 35.3 years. The average duration of the nodules was 35.5 days. There was a history of contact tuberculosis in 16.6%. Constitutional symptoms and a strongly positive purified protein derivative (PPD) reaction were found in 66.6%. Chest roentgenograms were abnormal in 83.3%. The erythrocyte sedimentation rate was elevated in all tested cases. The histopathologic diagnoses were nodular vasculitis (33.3%), erythema nodosum (50%), and cutaneous periarteritis nodosa (16.4%). The panniculitis lesion responded to standard antituberculous regimens in 4.6 weeks, on average, with residual hyperpigmentation. CONCLUSIONS: In panniculitis patients, clues for the investigation of tuberculosis included constitutional symptoms, elevated erythrocyte sedimentation rate, and abnormal chest roentgenograms. Histopathologic changes of panniculitis did not seem to correlate with underlying tuberculosis. The clinician should be aware of the tuberculosis, however, and should carefully search for active foci in all panniculitis patients.

Stevens-Johnson syndrome and toxic epidermal necrolysis in Thailand.

BACKGROUND: Stevens-Johnson syndrome (SJS) and toxic epidermal necrolysis (TEN) are potentially life-threatening illnesses that have often been linked to drug exposure. METHODS: We looked retrospectively for all cases of SJS and TEN that were admitted to Siriraj Hospital between 1981 and 1990 to determine the drug etiology. RESULTS: Fifty-eight cases of SJS and 20 cases of TEN were identified. Eight patients initially had an SJS-like aspect, which subsequently evolved into TEN. A culpable drug was determined in 60 patients (77%). The mean time from first drug administration to onset of SJS or TEN was 6.8 +/- 6.5 days (range, 1 to 28 days). A longer incubation period was observed with thiacetazone (10.5 +/- 5.6 days), phenytoin (12 +/- 8.5 days), and carbamazepine (11.3 +/- 3.4 days). CONCLUSIONS: The culprit drugs included the following: antibiotics, 32 cases (penicillin, sulfonamides, tetracycline, erythromycin); anticonvulsants, nine (phenytoin, carbamazepine, barbiturates); antitubercular drugs, eight (thiacetazone); analgesics, four (acetylsalicylic acid, fenbufen); sulfonylurea, two; allopurinol, one; and others, four. The most frequent underlying diseases justifying the ingestion of one or more drugs in our patients were infections (52.7%), followed by pulmonary tuberculosis (10.8%), and by seizures (8.1%). The total mortality rate was 14%; 5% for SJS, and 40% for TEN. Mortality was not affected by the type of drug responsible.

Association of Fcgamma receptor IIb and IIIb polymorphisms with susceptibility to systemic lupus erythematosus in Thais.

We recently reported association of a newly identified polymorphism of Fcgamma receptor (FcgammaR) IIb, I232T, with systemic lupus erythematosus (SLE) in Japanese. To date, information on FcgammaR genotypes and their association with SLE is limited in South-east Asian populations. To gain further insight into the role of FcgammaR polymorphisms in the genetic predisposition of SLE, association of FcgammaRIIa-H131R, IIb-I232T, IIIa-F176V and IIIb-NA1/NA2 (HNA-1a/1b) polymorphisms with SLE was analyzed in the Thai population, using case-control association analysis. FcgammaRIIb-232T/T and IIIb-NA2/NA2 genotypes were associated with SLE with the odds ratio of 2.55. Genotype relative risk analysis revealed significant association of IIb-232T/T and IIIb-NA2/NA2, and a tendency of association of the IIIa-176F/F genotype. Moreover, carriers of FcgammaRIIa-131R were significantly increased in patients with lupus nephritis. Significant linkage disequilibrium was present among FcgammaRIIb, IIIa and IIIb, and two-locus analyses suggested that the tendency of association of FcgammaRIIIa could derive from linkage disequilibrium with IIb and IIIb. These results provided evidence that FcgammaR polymorphisms may be an important predisposing factor also in Thais in a complex manner.

Association of HLA-DRB1*1502-DQB1*0501 haplotype with susceptibility to systemic lupus erythematosus in Thais.

In this study, we investigated the association of HLA-DRB1 and DQB1 with Thai patients with SLE. A highly significant increase in the frequency of DRB1*1502 and DQB1*0501 was found in SLE patients compared with normal controls. DRB1*1501 and DRB1*1602 were also slightly increased. In contrast, DRB1*1202 and DQB1*0301 were decreased, and DRB1*0406 and DRB1*1401 were not found in the patients' group. The haplotype analysis revealed that DRB1*1502 - DQB1*0501 was most strongly associated with SLE, and also suggested a primary role for DRB1 rather than DQB1. Taken together with the previous report which demonstrated the association of the same haplotype in Taiwan, our present observations strongly suggested that DRB1*1502 - DQB1*0501 is the major HLA haplotype that confers susceptibility to SLE in the South-east Asian populations.