Body mass index and the incidence of influenza-associated pneumonia in a UK primary care cohort.

BACKGROUND: Accumulating data suggest an association between increased BMI/obesity and morbidity in patients with pandemic (H1N1) 2009 influenza. Information on metabolic status and prognosis in seasonal influenza is lacking, however. METHODS: A retrospective cohort study was carried out using the UK General Practice Research Database. Patients aged ≥18 with ≥1 recorded BMI in the 12-58 kg/m(2) range between January 1, 2000, and December 31, 2007, were observed for an influenza-associated pneumonia diagnosis after the date of baseline BMI, including 'influenza with pneumonia' or a diagnosis of 'pneumonia' up to 30 days after a diagnosis of 'influenza'. RESULTS: A total of 1,074,315 patients were included, of whom 73·2% were within the reference BMI range or overweight and 2·2% were underweight (<18·5 kg/m(2)). Pneumonia rates were 32·33-37·48/100,000 in all BMI categories except the underweight (98·29/100,000). Relative to patients with acceptable weight, those who were underweight had an increased pneumonia rate [adjusted IRR = 2·32 (95% CI 1·80-2·94)], while being overweight (BMI = 25·0-29·9 kg/m(2)) or obese (BMI ≥ 30·0 kg/m(2)) was associated with a decreased pneumonia rate [adjusted IRR = 0·77 (95% CI 0·68-0·86) and 0·85 (95% CI 0·73-1·00), respectively]. On the other hand, women and obese women with type 2 diabetes had increased pneumonia rates [adjusted IRR = 1·37 (95% CI 1·08-1·72) and 1·47 (95%CI 1·01-2·06), respectively]. CONCLUSIONS: In contrast to initial data from pandemic influenza, influenza pneumonia, and pneumonia following influenza were the most common in underweight persons, and an apparent decreased rate of pneumonia was noted with increasing BMI categories. Women with type 2 diabetes had increased rates of pneumonia.

Safety profile of oseltamivir during the 2009 influenza pandemic.

PURPOSE: This study evaluated the safety of oseltamivir during the 2009 influenza pandemic. METHODS: Case reports were obtained from the Roche safety database. The incidence of adverse events (AEs) during the pandemic (1 May 2009 to 31 December 2009) was compared with that beforehand (during previous influenza seasons) for USA and Japan only, as exposure data in other countries were collected inconsistently. Events with significantly higher reporting during the pandemic (lower bound of 95%CI for crude rate ratio >1) were analyzed further. RESULTS: Global exposure in the pandemic and prepandemic periods was 18.3 and 64.7 million patients, respectively. In USA and Japan, exposure was 15.5 (1382 cases, 2225 events) and 62.0 million (8387 cases, 12,749 events), respectively. AEs with significantly higher reporting during the pandemic were generally consistent with influenza and its complications and/or with the circulation of a novel virus strain. As might be expected in a pandemic, mortality increased (crude rate ratio, 2.83; 95%CI, 2.23-3.59) versus the prepandemic period. Medical review of serious AEs (fatal or non-fatal outcome) found that most were consistent with pre-existing risk factors, underlying disease, and/or progression of influenza or its complications. Analysis of the remainder did not suggest a causal link with oseltamivir. A review of AEs in previously underexposed subpopulations did not support an association with oseltamivir. CONCLUSIONS: During the first 8 months of the 2009 influenza pandemic, AEs reported in patients exposed to oseltamivir were consistent with the drug's labeled safety profile, underlying medical conditions, or infection with the pandemic virus.

Skin, soft tissue, bone, and joint infections in hospitalized patients: epidemiology and microbiological, clinical, and economic outcomes.

BACKGROUND: Infections involving skin, soft tissue, bone, or joint (SSTBJ) are common and often require hospitalization. There are currently few published studies on the epidemiology and clinical and economic outcomes of these infections, whether acquired in the community or healthcare setting, in a large population. OBJECTIVE: To characterize outcomes of culture-proven SSTBJ infection in hospitalized patients, using information from a large database. DESIGN: We identified patients hospitalized in 134 institutions during 2002-2003 for whom specific International Classification of Diseases, Ninth Revision, Clinical Modification diagnosis codes and a culture-positive SSTBJ specimen were recorded. Patients were classified into 4 clinical groups based on the type and clinical severity of infection. Patients in each group were further classified on the basis of whether their infection was community acquired or healthcare associated and whether it was complicated or uncomplicated. RESULTS: We identified 12,506 patients with culture-positive infections and categorized them as having cellulitis (37.3%), osteomyelitis or septic arthritis (22.4%), surgical wound infection (26.1%), device-associated or prosthesis infection (7.2%), or other SSTBJ infection (6.9%). Monomicrobial infection was reported for 59% of patients, 54.6% of whom had Staphylococcus aureus as the etiologic agent. Of all S. aureus isolates recovered, 1,121 (28.0%) of 4,007 were resistant to methicillin. Healthcare-associated infections accounted for 27.2% of cases and were associated with a significantly greater mortality rate, a longer length of stay, and greater hospital charges, compared with community-acquired infections. Patients with a complicated infection (78.4%) had a significantly greater mortality rate, a longer length of stay, and greater hospital charges, compared with patients with an uncomplicated infection. CONCLUSIONS: SSTBJ infections are frequent among hospitalized patients. S. aureus caused infection in more than 50% of the patients studied, and 28.0% of the S. aureus isolates recovered were resistant to methicillin. Healthcare-associated and complicated infections are associated with a significantly higher mortality rate and more prolonged and expensive hospitalizations. These findings could assist in projects to revise current management strategies in order to optimize outcomes while restraining costs.

Adverse outcomes from hospital-acquired infection in Pennsylvania cannot be attributed to increased risk on admission.

In July 2005, Pennsylvania became the first state in the nation to publicly report statewide data on hospital-acquired infections (HAI). The published research brief revealed that 11 668 hospitalizations with HAI had markedly different mortality rates, lengths of stay (LOS), and charges than cases without HAI did. To avoid a possibly biased comparison, a 5 to 1 propensity-matched cohort study was performed. Nine cohorts (ie, heart failure, chronic obstructive pulmonary disease, respiratory failure, pneumonia, hip fracture, major surgical complications, colonic resection, diabetes, and gastrointestinal bleeding) were examined for differences in mortality, LOS, and hospital charges. Statistically significant increases in mortality, LOS, and charges were found among HAI cases. HAI cases had more than a 4 times higher median charge than nonHAI controls did. Observed differences in mortality, LOS, and charges between HAI and non-HAI cases in Pennsylvania cannot be explained on the basis of increased disease-specific severity at the time of admission.

A population-based study of the incidence, cause, and severity of anaphylaxis in the United Kingdom.

BACKGROUND: Anaphylaxis is an acute and potentially fatal systemic reaction usually caused by mast cell-mediated release of histamine. Symptoms can vary in onset, appearance, and severity. Some common symptoms include weakness, dizziness, flushing, angioedema, urticaria, nasal congestion, and sneezing. Severe symptoms include upper respiratory tract obstruction, hypotension, vascular collapse associated with angioedema and urticaria, gastrointestinal distress, cardiovascular arrhythmias, and/or arrest. METHODS: We conducted an observational follow-up study encompassing approximately 8 million person-years based on the UK General Practice Research Database for the period January 1, 1994, to December 31, 1999, which quantified the frequency, type, and severity of a clinical diagnosis of anaphylaxis. RESULTS: Based on 675 cases of anaphylaxis, we estimate the incidence to be 8.4 per 100 000 person-years. Approximately 10% of cases had hypotension and shock that required urgent treatment. The most common causes were insect stings and oral medicines. CONCLUSION: Anaphylaxis is an uncommon illness that has multiple causes and can be life-threatening.

Genetic diversity of Cryptosporidium spp. in cattle in Michigan: implications for understanding the transmission dynamics.

Epidemiological and molecular data on 248 bovine, 17 human, and 16 water samples of Cryptosporidium spp. collected from the lower peninsula of Michigan between 1997 and 2000 were analysed. Cryptosporidium parvum bovine genotype and Cryptosporidium andersoni were found in 56 and four cattle samples, respectively. A total of six C. parvum subgenotypes were found in 34 bovine samples, and five of the eight farms had two or three subgenotypes in cattle. Six water samples from these farms had C. andersoni, five had the C. parvum bovine genotype, and one had Cryptosporidium muris. In contrast, four PCR-positive human samples produced the C. parvum bovine genotype and two had the C. parvum human genotype. Among the C. parvum bovine genotype samples, two human samples and one water sample had subgenotypes identical to those found on cattle farms. The results of this study demonstrate the potential use of molecular methods in tracking the transmission of Cryptosporidium.

Molecular epidemiology of cryptosporidiosis in children in Malawi.

Few studies have examined the molecular epidemiology of cryptosporidiosis in developing countries. In this study, DNA of 69 microscopy-positive human fecal samples collected from Malawi were examined by multilocus genetic analyses. From 43, 27 and 28 of the samples, the SSU rRNA, 70 kDa heat shock protein (HSP70) and 60 kDa glycoprotein (GP60) genes, respectively, were successfully PCR-amplified. Restriction analysis of the SSU PCR products showed that 41 of the 43 PCR-positive samples had C. hominis and 2 had C. parvum. Sequence analysis of the HSP70 and GP60 gene confirmed the species identification by SSU rRNA PCR-RFLP analysis, but also revealed high intraspecific variations. Altogether, six HSP70 subtypes and six GP60 subtypes (belonging to four subtype alleles) of C. hominis were found. Linkage disequilibrum analysis of the two genetic loci showed possible intraspecific recombination. Thus, cryptosporidiosis in the study area was largely caused by anthroponotic transmission. The high intraspecific variation and existence of genetic recombination were probably results of high transmission of cryptosporidiosis in this area.