Peritonitis due to Prototheca wickerhamii in a patient undergoing chronic ambulatory peritoneal dialysis

A 72-year-old man who was undergoing chronic ambulatory peritoneal dialysis developed peritonitis due to Prototheca wickerhamii. Results of in vitro sensitivity testing revealed that the organism was sensitive to amphotericin B (MIC, 0.4 micrograms/mL) but resistant to fluconazole (MIC, greater than 80 micrograms/mL). The patient was successfully treated medically with a combination of intravenous amphotericin B and oral doxycycline.     

Biological therapies for ulcerative colitis

Biological therapies are being increasingly investigated for the treatment of inflammatory bowel disease. However, a great deal more study has been devoted to studies of Crohn's disease rather than ulcerative colitis. Ulcerative colitis, like Crohn's disease, represents an area of high clinical need, particularly for those patients who have disease inadequately responsive to corticosteroids and 5-aminosalicylates. The distinct anatomic distribution of inflammation in ulcerative colitis represents an important model for study, with the entire involved mucosa entirely accessible to endoscopy. In addition, there is an opportunity for local delivery of biologic agents in left-sided disease. Distinct pathogenetic factors in ulcerative colitis raise the possibility of therapies quite different from those used in Crohn's disease. This work describes the current state of knowledge regarding biological therapy in ulcerative colitis. The role of probiotic therapy, and studies of cytokine-directed therapies, therapies targeting adhesion and recruitment, and restitution and repair are described.     

Predicting Clostridium difficile Stool Cytotoxin Results in Hospitalized Patients with Diarrhea

OBJECTIVE: To validate a model for the prediction of Clostridium difficile cytotoxin assay results, and to identify a subgroup of patients with a very low likelihood of C. difficile-associated disease in whom the yield of routine cytotoxin testing is low. DESIGN: Prospective cohort study. Relevant clinical symptoms, signs, and antibiotic exposure were recorded before reporting of assay results. Each predictor was assigned a score based on regression coefficients, and patients were stratified according to their total score. SETTING: Two urban, tertiary care, university hospitals. PATIENTS: A total of 609 consecutive adult inpatients who received testing for C. difficile cytotoxin during a 3-month period in 1994. MEASUREMENTS AND MAIN RESULTS: The prevalence of positive cytotoxin assays was 8% in the validation set, compared with 14% in the derivation set. Defining patients without both prior antibiotic use and at least one symptom predictor (significant diarrhea or abdominal pain) as a low-risk subgroup, the misclassification rate was 2.8% (5/177) for assay results; of the five misclassified cases patients, only one was judged to have C. difficile-associated disease. Use of this rule to identify low-risk patients could have potentially averted 29% of all cytotoxin assays. CONCLUSIONS: Exposure to role models in a particular clinical field is strongly associated with medical students' choice of clinical field for residency training. Knowing which characteristics students look for in their role models should help identify the physicians who may be most influential in medical students' career choice.     

A comparison of treatment planning techniques for low-dose-rate (LDR) prostate brachytherapy

PurposeThe purpose of this study was to compare low-dose-rate prostate brachytherapy treatment plans created using three retrospectively applied planning techniques with plans delivered to patients.Methods and MaterialsTreatment plans were created retrospectively on transrectal ultrasound (TRUS) scans for 26 patients. The technique dubbed 4D Brachytherapy was applied, using TRUS and MRI to obtain prostatic measurements required for the associated webBXT online nomogram. Using a patient's MRI scan to create a treatment plan involving loose seeds was also explored. Plans delivered to patients were made using an intraoperative loose seed TRUS-based planning technique. Prostate V₁₀₀ (%), prostate V₁₅₀ (%), prostate D₉₀ (Gy), rectum D_0.1cc (Gy), rectum D_2cc (Gy), urethra D₁₀ (%), urethra D₃₀ (%), and prostate volumes were measured for each patient. Statistical analysis was used to assess and compare plans.ResultsProstate volumes measured by TRUS and MRI were significantly different. Prostate volumes calculated by the webBXT online nomogram using TRUS- and MRI-based measurements were not significantly different. Compared with delivered plans, TRUS-based 4D Brachytherapy plans showed significantly lower rectum D_0.1cc (Gy) values, MRI-based 4D Brachytherapy plans showed significantly higher prostate V₁₀₀ (%) values and significantly lower rectum D_0.1cc (Gy), urethra D₁₀ (%), and urethra D₃₀ (%) values, and loose seed MRI-based plans showed significantly lower prostate V₁₀₀ (%), prostate D₉₀ (Gy), rectum D_0.1cc (Gy), rectum D_2cc (Gy), urethra D₁₀ (%), and urethra D₃₀ (%) values.ConclusionsTRUS-based 4D Brachytherapy plans showed similar dosimetry to delivered plans; rectal dosimetry was superior. MRI can be integrated into the 4D Brachytherapy workflow. The webBXT online nomogram overestimates the required number of seeds.     

Bottom-up analysis of emergent properties of N-acetylcysteine as an adjuvant therapy for COVID-19

N-acetylcysteine (NAC) is an abundantly available antioxidant with a wide range of antidotal properties currently best studied for its use in treating acetaminophen overdose. It has a robustly established safety profile with easily tolerated side effects and presents the Food and Drug Administration's approval for use in treating acetaminophen overdose patients. It has been proven efficacious in off-label uses, such as in respiratory diseases, heart disease, cancer, human immunodeficiency virus infection, and seasonal influenza. Clinical trials have recently shown that NAC's capacity to replenish glutathione stores may significantly improve coronavirus disease 2019 (COVID-19) outcomes, especially in high risk individuals. Interestingly, individuals with glucose 6-phosphate dehydrogenase deficiency have been shown to experience even greater benefit. The same study has concluded that NAC's ability to mitigate the impact of the cytokine storm and prevent elevation of liver enzymes, C-reactive protein, and ferritin is associated with higher success rates weaning from the ventilator and return to normal function in COVID-19 patients. Considering the background knowledge of biochemistry, current uses of NAC in clinical practice, and newly acquired evidence on its potential efficacy against COVID-19, it is worthwhile to investigate further whether this agent can be used as a treatment or adjuvant for COVID-19.     

Response patterns of purified myeloma cells to hematopoietic growth factors

Tumor cells were isolated from the bone marrow of seven patients with multiple myeloma and from the peripheral blood of three patients with plasma cell leukemia using Ficoll-Hypaque (FH) density sedimentation followed by immune rosette depletion of T, myeloid, monocytoid, and natural killer (NK) cells. Enrichment to greater than or equal to 93% plasma cells was confirmed with Wright's-Giemsa staining, with intracytoplasmic immunoglobulin staining, and with staining using monoclonal antibodies (MoAbs) directed at B, T, myeloid, monocytoid, and myeloma antigens in indirect immunofluorescence assays. Myeloma cells neither proliferated nor secreted Ig in response to G/M-CSF, G- CSF, M-CSF, interleukin-1 alpha (IL-1 alpha), interleukin-1 beta (IL-1 beta), interleukin-2 (IL-2), or interleukin-4 (IL-4). Significant proliferation (SI greater than or equal to 3.0) was induced by interleukin-6 (IL-6) in six of ten patients (SI of 31 and 43 in two cases); and to interleukin-3 (IL-3) and interleukin-5 (IL-5), independently, in two patients each. Peak proliferation to IL-5 or IL-6 and to IL-3 occurred in cells pulsed with 3[H] thymidine at 24 and 48 hours, respectively; and proliferation to combinations of factors did not exceed that noted to IL-6 alone; Ig secretion was not documented under any culture conditions. Three myeloma-derived cell lines similarly studied demonstrated variable responses. The heterogeneity in the in vitro responses of myeloma cells and derived cell lines to exogenous growth factors enhances our understanding of abnormal plasma cell growth and may yield insight into the pathophysiology of plasma cell dyscrasias.     

A cross-sectional study of growth,nutritional status and body proportions in children and adolescents at a medical center specializing in the treatment of cystic fibrosis in Poland

Introduction

Malnutrition, delayed growth and delayed puberty are commonly seen in children with cystic fibrosis. The aim of this study was to evaluate growth, nutritional status and body proportions in children and adolescents suffering from cystic fibrosis.

Material and methods

The evaluation was based on 19 somatic measurements and indices calculated from these measurements. Somatic development was evaluated in relation to several factors connected to the clinical picture or the course of the disease. Anthropometric data were extracted from the medical histories of 41 boys and 48 girls diagnosed and treated at the Institute of Mother and Child in Warsaw (Poland). Mean values for somatic parameters and body build indices for the children suffering from CF were compared to those for the reference group.

Results

The results revealed that growth in these children was significantly delayed in comparison to that seen in the healthy population (Z-score = –0.56, p < 0.001). Nutritional status was also adversely affected (Z-score = –0.85, p < 0.001). The children suffered more from a deficit in muscularity than in adiposity (Z-score = –0.75 and Z-score = –0.34, p < 0.01, respectively). This was especially true for boys. The children had infantile body proportions and defects in trunk and chest structure.

Conclusions

The factors that most affected somatic development were infection by Pseudomonas aeruginosa and the time at which the disease was diagnosed. Chronic infection by P. aeruginosa and type of CFTR mutation were the factors that most affected pulmonary function parameters.