Thymic cysts in mediastinal Hodgkin disease

Three cases of proved thymic cysts associated with mediastinal Hodgkin disease are presented. Two illustrate regression of lymphoma with chemotherapy but persistence of thymic cysts. The third case demonstrates a thymic cyst in untreated Hodgkin disease. These cases suggest that such cysts are probably neither coincidental with nor a consequence of therapy but are probably related to initial thymic involvement by Hodgkin disease.     

Effects of premium discount on workers' compensation claims in agriculture in Finland

BACKGROUND: The objective of this study was to measure changes in injury claim rates after a premium discount program was implemented in the Finnish farmers' workers' compensation insurance. We focused on measures that could indicate whether the changes occurred in the true underlying injury rate, or only in claims reporting. METHODS: Monthly injury claim rates were constructed at seven disability duration levels from January 1990 to December 2003. We conducted interrupted time series analyses to measure changes in the injury claim rates after the premium discount was implemented on July 1, 1997. Three additional policy change indicators were included in the analyses. RESULTS: The overall injury claim rate decreased 10.2%. Decreases occurred at four severity levels (measured by compensated disability days): 0 days (16.3%), 1-6 days (14.1%), 7-13 days (19.5%), and 14-29 days (8.4%). No changes were observed at higher severity levels. Minor injuries had a seasonal pattern with higher rates in summer months while severe injuries did not have a seasonal pattern. CONCLUSIONS: The premium discount decreased the overall claim rate. Decreases were observed in all categories up to 29 disability days. This pattern suggests that under-reporting contributes to the decrease but may not be the only factor. The value of the premium discount is lower than the value of a lost-time claim, so there was no financial reason to under-report lost-time injuries. Under-reporting would be expected to be greatest in the 0 day category, but that was not the case. These observations suggest that in addition to under-reporting, the premium discount may also have some preventive effect.     

Hospitalization of children with acute immune thrombocytopenic purpura – is it necessary?

OBJECTIVE:

To identify a target group of children with acute immune thrombocytopenic purpura (ITP) that may not require hospitalization for management.

METHODS:

A retrospective chart review was conducted of all children admitted over a two-year period to a tertiary care paediatric hospital with the diagnosis of acute ITP. Patients were classified according to typical and atypical presentations. Typical patients were defined as those aged between one and 10 years, with no hepatomegaly or significant splenomegaly and who had typical laboratory features for ITP. Patients who did not meet these criteria were categorized as atypical. Outcome measures included length of stay (LOS) in hospital; frequency of bone marrow aspiration (BMA); type of treatment; incidence of intracranial hemorrhage (ICH) or severe bleeding; and admission and discharge platelet counts.

RESULTS:

There were 74 patients hospitalized for a mean of 3.6 days. No patients suffered an ICH or bleeding requiring transfusion. Patients with typical presentations (42) were compared with patients with atypical presentations (32) and were not significantly different for clinically important outcomes such as admission and discharge platelet counts, serious complications or type of therapy. Typical patients had significantly fewer BMAs than did atypical patients – 22 of 42 (52%) versus 25 of 32 (78%) (P=0.02), and a shorter LOS – 3.1 (±0.9) days versus 4.2 (±1.8) days (P=0.01).

CONCLUSIONS:

Children presenting with ITP have a low incidence of bleeding complications and many of these patients can be managed as outpatients. A multicentre study is needed to properly delineate a low risk group suited for outpatient medical management.     

Farm-related dermatoses in Iowa male farmers and wives of farmers: a cross-sectional analysis of the Iowa Farm Family Health and Hazard Surveillance Project

Agricultural workers are exposed to a variety of hazards that increase their risk for dermatitis. Nevertheless, the prevalence, patterns, and risk factors for dermatitis have not been well characterized among farmers in the United States. We assessed the prevalence and risk factors for dermatitis among 382 male farmers and 256 wives of farmers in Iowa using a cross-sectional study design. From 1992 to 1994, we collected data on potential risk factors and dermatitis. The results showed that 9.6% of male farmers and 14.4% of wives of farmers reported dermatitis during the previous 12-month period. In multivariable models, a history of allergy (odds ratio [OR], 8.2; 95% confidence interval [CI], 2.0 to 33.3) was strongly associated with dermatitis among male farmers. Among wives of farmers, some college education (OR, 3.4; 95% CI, 1.1 to 9.9) and exposure to petroleum products (OR, 3.1; 95% CI, 1.3 to 7.0) were associated with dermatitis. These results can be used to form preventive efforts in controlling farmwork-related exposures.     

Calorie restriction in nonhuman primates: mechanisms of reduced morbidity and mortality

Long term chronic calorie restriction (CR) of adult nonhuman primates significantly reduces morbidity and increases median age of death. The present review is focused upon an ongoing study of sustained adult- onset calorie restriction, which has been underway for 15 years. Monkeys, initially calorie restricted at about 10 years of age, are now approximately 25 years old. The median life span of these restricted monkeys is increasing, now exceeding that of ad libitum (AL)-fed monkeys. In our laboratory, maximum life span for AL-fed monkeys appears to be about 40 years. Thus, whether CR can also increase maximal life span, as it does in rodents, cannot be determined for at least another 15 years. The earliest detectable positive benefit on morbidity in these monkeys was previously reported as the prevention of obesity. Current evidence, as reviewed here, suggests that much obesity- associated morbidity is also mitigated by sustained calorie restraint in nonhuman primates. Furthermore, probably because of the prevention of obesity, diabetes has also been prevented. Recent findings include the identification of extraordinary changes in the glycogen synthesis pathway, and on the phosphorylation of glycogen synthase in response to insulin. This calorie restriction-induced prevention of morbidity does not require excessive leanness, but is clearly present when body fat is within the normal range of 10 to 22%, and this is likely to be true in humans as well.      

Speech-controlled generation of radiology reports

Voice entry has been successfully employed to generate radiology reports with a word recognizer with a 1,000-word lexicon capacity. About 50% of reports were able to be dictated with a single 900-word lexicon. This was split into five sections by anatomic or subspecialty application. Each was augmented to 900 words. By switching from one lexicon to another, it was possible to dictate more than 70% of reports. With exclusive use of three lexicons in subspecialty areas (gastrointestinal radiology, neuroradiology, and mammography), and with further modification of the respective vocabulary, it has been possible to employ the system 88% of the time. Twelve percent of cases included wording that was beyond the scope of the lexicon. Computer subsets that allow different translations of some words when used in different contexts have been used. Some of these are used as triggers that will print whole lines, sentences, or even complete reports. Dictation times with voice entry take about 20% longer. Recognition reliability has been greater than 95%.     

Thrombopoietin stimulates colony-forming unit-megakaryocyte proliferation and megakaryocyte maturation independently of cytokines that signal through the gp130 receptor subunit

Thrombopoietin (Tpo), the ligand for the c-Mpl receptor, is a major regulator of megakaryopoiesis. Treatment of mice with Tpo raises the platelet count fourfold within a few days. Conversely, c-mpl knock-out mice have platelet counts that are 15% that of normal. The subunit structure of the c-Mpl receptor is not fully understood. Some cytokines that stimulate megakaryopoiesis (IL-6, IL-11, leukemia inhibitory factor, and oncostatin M) bind to receptors that use gp130 as a signal transduction subunit. For these reasons, we determined whether gp130 function was required for Tpo-induced signal transduction. Murine marrow cells were cultured in semi-solid media in the presence of Tpo or IL-3, with or without a neutralizing anti-gp130 monoclonal antibody (RX187) or a soluble form of c-Mpl receptor (soluble Mpl) that blocks Tpo bioactivity, and the numbers of colony-forming unit-megakaryocyte (CFU-Meg) colonies were counted on day 5. Murine marrow cells were also cultured in suspension under serum-free conditions for 5 days, and megakaryocyte DNA content was measured by flow cytometry, as an index of nuclear maturation. The addition of RX187 did not block Tpo-induced CFU-Meg colony growth nor CFU-Meg nuclear maturation in suspension culture. However, IL-3-induced CFU-Meg colony growth and megakaryocyte nuclear maturation decreased in the presence of RX187. Soluble Mpl completely ablated Tpo-induced CFU-Meg growth, and partially blocked IL- 3-stimulated CFU-Meg growth. Thus the effects of Tpo on megakaryopoiesis in vitro do not depend on cytokines that signal through gp130. Furthermore, it is unlikely that gp 130 serves as a beta chain for the c-Mpl receptor, as Tpo signalling is unimpaired in the presence of RX187. In contrast, the effects of IL-3 on CFU-Meg growth are mediated in part through Tpo and through gp130-signalling cytokines.     

Noncardiogenic pulmonary edema caused by decompression sickness: rapid resolution following hyperbaric therapy

Noncardiogenic pulmonary edema is a recognized but uncommon manifestation of type 2 decompression sickness. It typically occurs within 6 hours of a dive. Because the adult respiratory distress syndrome in this setting is believed to be due to microbubbles in the pulmonary vasculature, recompression in a hyperbaric chamber has been recommended as a form of therapy. A patient developed noncardiogenic pulmonary edema following a seawater dive to 75 feet. There was complete radiologic and clinical resolution within 5 hours of hyperbaric therapy.     

Pulmonary histiocytosis X: comparison of radiographic and CT findings

The authors retrospectively evaluated radiographs, computed tomographic (CT) scans, and results of pulmonary function tests (when available) for 17 patients with biopsy-proved pulmonary histiocytosis X. In 11 patients, high-resolution CT was used. In 12 patients, CT demonstrated cystic air spaces, usually less than 10 mm in diameter. In three of these 12, cysts were the only abnormality, but in six others, nodules (usually less than 5 mm in diameter) were also present. Two patients had only nodules and one, only emphysema. CT showed that many lesions that appeared reticular on plain radiographs were actually cysts. CT showed no central or peripheral concentration of lesions, but it did reveal that many small nodules were distributed in the centers of secondary lobules around small airways. CT findings correlated better with the diffusing capacity (rho = -0.71) than did the plain radiographic findings (rho = -0.57). Thus, CT was better than radiography at showing the morphology and distribution of lung abnormalities.