Juvenile dermatomyositis and polymyositis: a follow-up study of long-term sequelae.

BACKGROUND: Juvenile dermatomyositis/polymyositis (DMS/PM) are childhood inflammatory myopathies that normally affect children between 2 and 15 years of age. The disease is manifested as severe proximal muscle weakness and, in JDMS, as a characteristic cutaneous eruption. It is difficult to predict the course of the disease. This study is aimed at objectively assessing the long-term morbidity of dermatomyositis/polymyositis in children. METHODS: Twelve cases of JDMS/PM identified through chart review were evaluated by physical and dermatologic examination, muscle testing, ultrasonography, and magnetic resonance imaging (MRI). RESULTS: The patient population included 6 male and 6 female patients with a mean age of 18.8 years (standard deviation 12.4). The mean age at onset of JDMS/PM was 5.8 years (SD 2.8), and the mean time from onset of symptoms to beginning of the study was 10.1 years (SD 9.3). The mean duration of corticosteroid therapy was 53.1 months (SD 40.5), with patients reporting an average of 1.7 relapses (SD 1.5). Patients compared their own activity level with that of healthy control subjects, and on a scale of 1 to 5 with 5 being normal, their mean score was 3.9 (SD 0.9). Fifty-eight percent of the patients had at least one residual finding on physical examination, and 78% of those with JDMS had residual dermatologic sequelae. Despite these findings, the mean grade for the group was 4.6 (SD 0.6) for muscle strength, using a scale of 0 to 5 with 0 being no muscle resistance and 5 being normal. In 60% of patients examined by ultrasonography, increased echogenicity indicated possible residual fibrotic change in at least one muscle group. Although MRI showed no active disease process in four patients, scattered intramuscular calcification was found in one patient. CONCLUSIONS: Multiple physical and dermatologic sequelae are commonly present in patients with JDMS/PM on long-term follow-up, but these do not preclude a productive life. Ultrasonography and MRI provide additional noninvasive means of analysis, but because of the current high cost, MRI is not routinely recommended.

Comparative analysis of precipitating antibodies in White Rock and Fayoumi hens injected with bovine serum albumin or crude mite extract with resulting effects on northern fowl mite, Ornithonyssus sylviarum (Acari: Macronyssidae) population densities.

Precipitating antibody concentration responses to crude northern fowl mite extract (CME) and bovine serum albumin (BSA) injections were compared in White Rock and Fayoumi hens with two-dimensional immunoelectrophoresis and rocket electrophoresis. The effect of CME injections on northern fowl mite population development was also determined. White Rock and Fayoumi hens developed similar antibody concentrations in response to intramuscular injections of BSA according to serum samples analyzed with two-dimensional immunoelectrophoresis. Rocket electrophoresis analyses of pooled serum samples showed significant differences between slopes of White Rock and Fayoumi pools for CME and BSA injections, suggesting differences in antibody-antigen interactions. Fayoumi hens injected with CME, 78, 50, and 14 days prior to experimental infestation with 2,000 northern fowl mites/bird supported significantly fewer mites than BSA-injected hens, although mite populations were low on both treatment groups. Injections of CME had no effect on mite population development on White Rock hens, even though CME-specific antibodies were detected. Although White Rock hens supported significantly greater mite numbers than Fayoumi hens, the difference was not attributed to anti-CME antibody activity alone.

Manure pit temperatures and relative humidity of Pennsylvania high-rise poultry houses and their relationship to arthropod population development.

Air temperature and relative humidity (RH) in the manure pits of five central Pennsylvania high-rise poultry houses were measured for at least one year to evaluate the role of the pit environment in the development of manure breeding flies and litter beetles. Pit air temperatures had weekly means ranging between 18.1 and 22.2 C. Seasonal temperature trends were similar at all farms, decreasing in winter and rising in summer. Maximum pit temperatures ranged from 31.7 to 33.3 C and minimum temperatures from .6 to 5.6 C, but these extremes were rare. Three houses had weekly mean RH ca 65%, one ca 61%, and one ca 72%. No seasonal RH trends were evident. Daily temperature fluctuations were lowest at ca 0600 to 0700 h, peaked ca 1700 h, and varied inversely with RH. Pit air temperatures dropped below house fly reproductive thresholds for several weeks during the winter, but were adequate for their survival all year around. Manure temperatures were affected by the shape of the manure pile, depth of the manure, and seasonal air temperature patterns. Manure temperatures differed significantly between houses with either shallow (without scraper boards, mean ca 16 to 19 C) or deep (with scraper boards, mean ca 30 to 40 C) manure profiles. Shallow manure profile temperatures severely limit fly larvae and litter beetle development.

An evaluation of permethrin, carbaryl, and amitraz for the control of northern fowl mites on caged chickens.

In two trials at the University poultry farm, two formulations of the synthetic pyrethroid permethrin (Ectiban 5.0% EC and Ectiban .25% Livestock Dust) were compared against carbaryl and amitraz sprays for the control of northern fowl mite, Ornithonyssus sylviarum (Canestrini and Fanzago), on caged birds. Under continuous reinfestation pressure, birds treated with dust did not support live mites in the vent region until 7 weeks posttreatment in comparison to 4 weeks with the permethrin 0.5% spray. Initially, both carbaryl (.5%) and amitraz (0.5%) sprays were as effective in controlling mites as the permethrin spray but did not provide protection for as long a period. Individual birds were either had dusted or treated with low pressure sprays.