Skin Colonizers and Catheter Associated Blood Stream Infections in Incident Indian Dialysis Patients.

Introduction: Skin colonization is a risk factor for multi-drug resistant (MDR) catheter-associated bloodstream infections (CABSI). This study aimed to determine the prevalence and spectrum of skin colonizing MDR organisms in incident HD patients and their correlation with CABSI. Methods: This single-center prospective cohort study included consecutive adult incident HD patients who underwent tunneled or non-tunneled internal jugular vein HD catheter insertion between June 1, 2017 and October 31, 2017. Nasal, axillary, and exit site swabs were obtained prior to catheter insertion, at 14-21 days, and 28-35 days after catheter insertion. Results: Forty-three patients (69.7% male, 32.5% diabetic) were included and provided baseline swabs, while 29 and 10 patients respectively were available for follow-up swabs. MDR bacterial colonization, MRSA colonization, and MDR gram-negative colonization on the baseline set of swabs were seen in 76.7%, 69.7%, and 9.3% patients respectively. Of the 29 patients with at least two consecutive sets of swabs, 79.3% showed persistent colonization by MDR gram-positive organisms, most commonly by MRSA. Six patients developed a CABSI during the follow-up period (incidence rate 3.7 per 1000 patient days), 83.4% were gram negative, and in only one instance (16.6%) was the bacterial strain identical to that which had previously colonized the skin. Conclusions: Three-fourths of HD patients were colonized by MDR bacteria prior to HD initiation. Despite the majority being persistently colonized by MDR gram-positive organisms, CABSIs were predominantly gram negative.

Infection-Associated Peripheral Nerve Hyperexcitability: An Under-Recognized Entity.

BACKGROUND: Peripheral nerve hyperexcitability (PNH) and neuromyotonia have been mainly attributed to antibodies against voltage-gated potassium channels (VGKC). Concurrent autoimmune disorders, malignancies, and heavy metal toxicity have also been implicated. There is scarce mention about infection as a triggering factor for PNH. There are no reports of methicillin-resistant Staphylococcus aureus (MRSA) infection being a possible precipitating factor for development of PNH. METHODS: Case series and literature review. RESULTS: Four subjects were diagnosed to have features of PNH based on clinical and electrophysiological assessment. All the subjects had concurrent evidence of cutaneous abscesses requiring surgical intervention and antibiotic therapy. The cultures in all of them revealed growth of Staphylococcus aureus with three of them being MRSA isolates. Two subjects tested positive for anti-VGKC antibodies. There was remarkable resolution in neuromyotonia after antibiotics in three subjects. One subject succumbed to fulminant MRSA septicemia. CONCLUSION: There appears to be a definitive link between staphylococcal infection (MRSA in particular) and development of PNH. The temporal evolution of PNH associated with the infection and resolution following treatment of the infection does support a causal association. The enterotoxins produced by staphylococci act as superantigens and could trigger an inflammatory cascade along with development of cross reacting antibodies against VGKC in peripheral nerves. Future studies with animal models could provide more directions in this regard.

Comparison of nested polymerase chain reaction and real-time polymerase chain reaction targeting 47kda gene for the diagnosis of scrub typhus.

Introduction: Scrub typhus is a zoonotic infection caused by Orientia tsutsugamushi which is transmitted by Leptotrombidium mites. The disease manifests as a mild-to-severe illness with non-specific clinical symptoms. Rapid diagnosis and prompt treatment are essential for patient management. Both serological and molecular methods are used for the diagnosis of scrub typhus. The present study assessed the usefulness of detection of the gene encoding the 47kDa outer-membrane protein (OMP) for the laboratory diagnosis of scrub typhus. Materials and Methods: Nested polymerase chain reaction (nPCR) and real-time PCR targeting 47 kDa OMP antigen gene of O. tsutsugamushi were performed on ethylenediaminetetraacetic acid blood samples. Results: Six of the 103 (5.8%) patients showed the presence of 47kDa gene by nPCR. Seventy of 103 (67.9%) cases showed the presence of 47kDa gene by qPCR. Among the 70 positive cases, the majority of them were females (40/70, 57.1%). The highest number of positive cases was observed during October-February. Conclusion: Real-time PCR targeting O. tsutsugamushi-specific 47-kDa gene is more sensitive than nPCR and may be the assay of choice for the detection of the organism in patients with suspected scrub typhus.

Microbiological profile of infections of the hip joint: An Indian perspective.

Background: Knowledge of the local microbiological epidemiology helps in formulating protocols for appropriate treatment of hip infections. The aim of this study was to profile the organisms cultured from infected hips. Methods: The microbiological profile and sensitivity pattern of organisms in eighty infected hips were reviewed. Results: Infection was secondary to arthroplasty in 35, fracture surgery in 34 and primary septic arthritis in 11. Twenty percent of the infections were polymicrobial, whereas the rest were monomicrobial. Fifty-five percent were Gram-positive, of which 45% were Staphylococcus species (36% methicillin-sensitive Staphylococcus aureus, 20% methicillin-resistant S. aureus, and 44% coagulase sensitive Staphylococcal species). All Staphylococcus species were sensitive to vancomycin, but 20% of Enterococcus species were resistant to vancomycin. One-third of the Enterococcus species and 2% of Staphylococcus species were resistant to teicoplanin. Escherichia coli (n = 10) and Pseudomonas sp. (n = 13) were the most common Gram-negative organism. Although 18% of the Gram-negative organisms were carbapenem resistant, all were sensitive to colistin. Conclusion: Staphylococcus sp. was the most common pathogen found in hip infections. However, the high incidence of Gram-negative infection requires that prophylactic antibiotics cover these organisms as well. The high resistance to first-line antibiotics should be taken into consideration while making protocols. The knowledge of the microbial profile is especially important when considering arthroplasty for arthritis secondary to hip infections.

Assessment of two immunoassays for detection of IgM antibodies to scrub typhus using a serum panel.

Laboratory tests are necessary for diagnosis of scrub typhus (ST) especially in the absence of the distinctive eschar. Performance of an ELISA and ICT (immunochromatography) to detect IgM antibodies to scrub typhus was assessed using a panel of 346 sera chosen from healthy individuals, those with scrub typhus and scrub-typhus like illness. A sensitivity of 98.7% for ST IgM ICT and 97.4% for ST IgM ELISA was observed while specificity was 96.3% for ICT and 95.9% for ELISA. As excellent concordance (98.8%) was noted between the two assays, IgM ICT can be used for rapid diagnosis of scrub typhus. Abbreviations: ST IgM ELISA: Scrub typhus IgM ELISA; ST IgM ICT: Scrub Typhus IgM Immunochromatography, Rapid diagnostic test: RDT.

Elevated procalcitonin is associated with increased mortality in patients with scrub typhus infection needing intensive care admission.

CONTEXT: Procalcitonin is a biomarker of bacterial sepsis. It is unclear if scrub typhus, a rickettsial illness, is associated with elevated procalcitonin levels. AIM: To assess if scrub typhus infection is associated with high procalcitonin levels and whether high levels portend a poorer prognosis. SETTING AND DESIGN: Retrospective study of patients with severe scrub typhus infection, admitted to the medical intensive care unit of a tertiary care university affiliated teaching hospital. MATERIALS AND METHODS: Eighty-four patients with severe scrub typhus infection that also had procalcitonin levels were assessed. STATISTICAL ANALYSIS: Relationship between procalcitonin and mortality explored using univariate and multivariate analyses. RESULTS: The mean (±standard deviation) age was 40.0 ± 15.5 years. Patients were symptomatic for 8.3 ± 4.3 days prior to presentation. The median admission procalcitonin level was 4.0 (interquartile range 1.8 to 8.5) ng/ml; 59 (70.2%) patients had levels >2 ng/ml. Invasive mechanical ventilation was required in 65 patients; 20 patients died. On univariate analysis, admission procalcitonin was associated with increased odds of death [odds ratio (OR) 1.09, 95% confidence interval (CI) 1.03 to 1.18]. On multivariate logistic regression analysis including procalcitonin and APACHE-II score, the APACHE-II score was significantly associated with mortality (OR 1.16, 95% CI 1.06 to 1.30, P = 0.004) while a trend was observed with procalcitonin (OR 1.05, 95%CI 1.01 to 1.13, P = 0.09). The area under the receiver operating characteristic (ROC) curve, AUC, for mortality was 0.77 for procalcitonin and 0.78 for APACHE-II. CONCLUSIONS: Procalcitonin is elevated in severe scrub typhus infection and may be associated with higher mortality.