A Systematic Review of Risk Factors Associated with Surgical Site Infections among Surgical Patients

Importance

Surgical site infection (SSI) complicates 2-5% of surgeries in the United States. Severity of SSI ranges from superficial skin infection to life-threatening conditions such as severe sepsis, and SSIs are responsible for increased morbidity, mortality, and economic burden associated with surgery. Staphylococcus aureus (S. aureus) is a commonly-isolated organism for SSI, and methicillin-resistant S. aureus SSI incidence is increasing globally.

Objective

The objective of this systematic review was to characterize risk factors for SSI within observational studies describing incidence of SSI in a real-world setting.

Evidence Review

An initial search identified 328 titles published in 2002-2012; 57 were identified as relevant for data extraction. Extracted information included study design and methodology, reported cumulative incidence and post-surgical time until onset of SSI, and odds ratios and associated variability for all factors considered in univariate and/or multivariable analyses.

Findings

Median SSI incidence was 3.7%, ranging from 0.1% to 50.4%. Incidence of overall SSI and S. aureus SSI were both highest in tumor-related and transplant surgeries. Median time until SSI onset was 17.0 days, with longer time-to-onset for orthopedic and transplant surgeries. Risk factors consistently identified as associated with SSI included co-morbidities, advanced age, risk indices, patient frailty, and surgery complexity. Thirteen studies considered diabetes as a risk factor in multivariable analysis; 85% found a significant association with SSI, with odds ratios ranging from 1.5-24.3. Longer surgeries were associated with increased SSI risk, with a median odds ratio of 2.3 across 11 studies reporting significant results.

Conclusions and Relevance

In a broad review of published literature, risk factors for SSI were characterized as describing reduced fitness, patient frailty, surgery duration, and complexity. Recognition of risk factors frequently associated with SSI allows for identification of such patients with the greatest need for optimal preventive measures to be identified and pre-treatment prior to surgery.     

Elevated risk for HIV infection among men who have sex with men in low- and middle-income countries 2000-2006: a systematic review

Background

Recent reports of high HIV infection rates among men who have sex with men (MSM) from Asia, Africa, Latin America, and the former Soviet Union (FSU) suggest high levels of HIV transmission among MSM in low- and middle-income countries. To investigate the global epidemic of HIV among MSM and the relationship of MSM outbreaks to general populations, we conducted a comprehensive review of HIV studies among MSM in low- and middle-income countries and performed a meta-analysis of reported MSM and reproductive-age adult HIV prevalence data.

Methods and Findings

A comprehensive review of the literature was conducted using systematic methodology. Data regarding HIV prevalence and total sample size was sequestered from each of the studies that met inclusion criteria and aggregate values for each country were calculated. Pooled odds ratio (OR) estimates were stratified by factors including HIV prevalence of the country, Joint United Nations Programme on HIV/AIDS (UNAIDS)–classified level of HIV epidemic, geographic region, and whether or not injection drug users (IDUs) played a significant role in given epidemic. Pooled ORs were stratified by prevalence level; very low-prevalence countries had an overall MSM OR of 58.4 (95% CI 56.3–60.6); low-prevalence countries, 14.4 (95% CI 13.8–14.9); and medium- to high-prevalence countries, 9.6 (95% CI 9.0–10.2). Significant differences in ORs for HIV infection among MSM in were seen when comparing low- and middle-income countries; low-income countries had an OR of 7.8 (95% CI 7.2–8.4), whereas middle-income countries had an OR of 23.4 (95% CI 22.8–24.0). Stratifying the pooled ORs by whether the country had a substantial component of IDU spread resulted in an OR of 12.8 (95% CI 12.3–13.4) in countries where IDU transmission was prevalent, and 24.4 (95% CI 23.7–25.2) where it was not. By region, the OR for MSM in the Americas was 33.3 (95% CI 32.3–34.2); 18.7 (95% CI 17.7–19.7) for Asia; 3.8 (95% CI 3.3–4.3) for Africa; and 1.3 (95% CI 1.1–1.6) for the low- and middle-income countries of Europe.

Conclusions

MSM have a markedly greater risk of being infected with HIV compared with general population samples from low- and middle-income countries in the Americas, Asia, and Africa. ORs for HIV infection in MSM are elevated across prevalence levels by country and decrease as general population prevalence increases, but remain 9-fold higher in medium–high prevalence settings. MSM from low- and middle-income countries are in urgent need of prevention and care, and appear to be both understudied and underserved.     

Genetic skeletal disorders of the fetus and infant: Pathologic and molecular findings in a series of 41 cases

BACKGROUND: Genetic skeletal disorders of the fetus and infant are a large group of genetic disorders, comprising the groups formerly assigned as skeletal dysplasias (osteochondrodysplasias), dysostoses, and malformation syndromes with a skeletal component. Genetic skeletal disorders may be prenatally detected by ultrasonography or result in intrauterine or early postnatal death, constituting one difficult diagnostic field met by the pathologist who performs the perinatal autopsy. METHODS: In this retrospective study, we have gathered radiologic, physical, histopathologic, and molecular data regarding 41 cases of genetic skeletal disorders diagnosed among 1980 fetal and perinatal autopsies over a 10‐year period. RESULTS: Our series of cases were classified according to the 2006 Nosology and Classification of Genetic Skeletal Disorders. The overall frequency of genetic skeletal disorders was 1:48 autopsies. The FGFR3 group and osteogenesis imperfecta type 2 were the more frequently encountered disorders. The mean gestational age at autopsy was 21.9 weeks (range, 12–37 weeks). A final diagnosis was obtained in 95% of cases. Genetic skeletal disorders were detected by prenatal ultrasound in 90% of cases, with a correct typing of the disorder achieved in only 34%. Molecular analysis was confirmative in 5 cases. CONCLUSIONS: The central role of the perinatal pathologist in collaboration with specialized services is essential for the correct interpretation of the radiologic, physical, and histopathologic findings, to accurately classify specific types of genetic skeletal disorders and enable genetic counseling. Birth Defects Research (Part A), 2009. © 2009 Wiley‐Liss, Inc.     

Improvement in spontaneous and acquired spatial behaviors following lesions of septal dopaminergic afferents in mice: possible relations with hippocampal cholinergic activity

Recent evidence from pharmacological studies support the view that dopaminergic afferents to the septal complex which originate from the mesencephalic A10 area, exert a tonic inhibitory control over the activity of the septal-hippocampal cholinergic neurons. Accordingly one could predict that the release from such an inhibition by lesion of the septal dopaminergic terminals might improve performance in tasks known to be related to hippocampal cholinergic activity. In order to test this hypothesis mice of the C57BL/6 strain received a bilateral injection of 6-hydroxydopamine in the lateral septal nucleus; they were compared to subjects receiving saline and to unoperated control mice in tests performed in a T-maze: spontaneous alternation, acquisition and reversal of spatial discrimination. In all tasks, performance of experimental subjects was improved relative to controls. However, subsequent experiments showed that this improvement was not observed when visual (light/dark) discrimination was used. Finally, 6-hydroxydopamine injected mice exhibited a substantial increase in hippocampal sodium-dependent high affinity choline uptake (+ 16.7%). These results are discussed in relation to the three main theories concerning the role of the septo-hippocampal complex and cholinergic system in the control of behavior (i.e. Pavlovian internal inhibition, spatial mapping and working memory). Only the theory of spatial cognition seems to account for our present findings.     

Toxoplasmosis in pregnant women in Crete

In Greece there are no official recommendations concerning the management of pregnant women for the prevention of congenital toxoplasmosis. A protocol for monitoring pregnant women was designed in order to differentiate between acute and latent toxoplasmosis and was tested successfully for 7 years. The maternofetal transmission rate in Crete was assessed and a map showing seroprevalence of pregnant women in all prefectures of Greece was prepared. The high seroprevalence of Toxoplasma gondii in Greece (up to 46% in some areas) may be explained by: (a) the presence of a great number of stray cats; (b) the Greek diet consisting of large amounts of raw, wild vegetables and salads that could easily be contaminated with oocysts; (c) the high consumption of meat, smoked pork and sausages, well-documented sources of T. gondii infection. T. gondii genotypes were characterized, directly from clinical samples, after PCR-RFLP on the SAG2 gene and sequence analysis at the restriction sites. They belonged to all 3 clonal lineages.