Diagnostic test accuracy of the BioFire® FilmArray® meningitis/encephalitis panel: a systematic review and meta-analysis.

BACKGROUND: The FilmArray® meningitis/encephalitis (ME) panel is a multiplex PCR assay which can detect the most commonly identified pathogens in central nervous system infections. It significantly decreases the time to diagnosis of ME and data has yielded several positive outcomes. However, in part, reports of both false positive and false negative detections have resulted in concerns about adoption. OBJECTIVES: The aim was to evaluate the ME panel in a diagnostic test accuracy review. DATA SOURCES: The PubMed and EMBASE databases were systematically searched through May 2019. STUDY ELIGIBILITY CRITERIA: Eligible studies were those providing sensitivity and specificity data for the ME panel compared with a reference standard. Studies providing details on false positive and false negative results of the panel as well as further investigation (adjudication) of the discordant results between the panel and comparator assays were included and assessed separately. PARTICIPANTS: Patients with suspected ME for whom a panel was ordered were included. METHODS: The ME panel was compared to reference standard methods for diagnosing community-acquired ME. We performed a meta-analysis and calculated the summary sensitivity and specificity of the ME panel. Moreover, we evaluated the false positive and false negative results of the panel. RESULTS: Thirteen studies (3764 patients) were included in the review and 8 of them (3059 patients) were pooled in a meta-analysis. The summary estimates of sensitivity and specificity with 95% confidence intervals (CI) was 90% (95% CI 86-93%) and 97% (95% CI 94-99%), respectively. When we looked specifically at studies that assessed further the false positive and false negative results, false positive detections were 11.4% and 4% before and after adjudication, respectively. The highest proportion of false positive was observed for Streptococcus pneumoniae followed by Streptococcus agalactiae. False negative isolates were 2.2% and 1.5% before and after adjudication, respectively. Herpes simplex virus 1 and 2, enterovirus and Cryptococcus neoformans/gattii had the highest proportions of false negative determinations. False negative C. neoformans/gattii were mostly patients with positive antigen titres, on treatment or cleared disease. CONCLUSIONS: The currently available literature suggests that the ME panel has high diagnostic accuracy. However, the decision for implementation should be individualized based on the needs of the patient population, the capabilities of the laboratory, and the knowledge of the healthcare providers that will utilize the test.

Abnormal vaginal flora in symptomatic non-pregnant and pregnant women in a Greek hospital: a prospective study.

Bacterial vaginosis (BV), candidiasis, and trichomoniasis were the three established types of vaginal conditions until aerobic vaginitis (AV) was defined in the early 2000s. We sought to study the prevalence of abnormal vaginal flora (AVF) with inflammation in our hospital and to correlate it with AV. We prospectively collected vaginal smear specimens originated from symptomatic women who were examined at Iaso Obstetrics, Gynecology and Children's Hospital of Athens from April 2014 until September 2015. Amsel's criteria were used for the diagnosis of BV. The presence of leukocytes and lactobacillary grade were evaluated to classify a condition as AVF with inflammation; subsequently, bacterial cultures were performed. A total of 761 women were included. Five hundred and seventy-nine women were diagnosed with candidiasis, BV, trichomoniasis, or other types of vaginitis in which no pathogenic bacterial growth occurred in cultures. One hundred and eighty-two women (23.9 %) were diagnosed with AVF with inflammation (116 non-pregnant, 66 pregnant). Escherichia coli was the most common pathogen among these women (non-pregnant: 45.7 %, pregnant: 34.8 %). Other common pathogens were Group-B-Streptococcus (non-pregnant: 20.7 %, pregnant: 22.7 % respectively), Enterococcus faecalis (14.7 %, 18.2 %), and Klebsiella pneumoniae (6.9 %, 12.1 %). The prevalence of AVF with inflammation may be high. Since inflammation criteria were applied, most cases of BV were eliminated and the majority of cases of AVF are AV. Therefore, clinicians should include AV in the differential diagnosis of vaginitis, while microbiologists should take into account the growth of aerobic bacteria in vaginal cultures originating from women with microscopic findings of AV.

Clostridium difficile in Crete, Greece: epidemiology, microbiology and clinical disease.

We studied the epidemiology and microbiology of Clostridium difficile and the characteristics of patients with C. difficile infection (CDI) in Crete in three groups of hospitalized patients with diarrhoea: group 1 [positive culture and positive toxin by enzyme immunoassay (EIA)]; group 2 (positive culture, negative toxin); group 3 (negative culture, negative toxin). Patients in group 1 were designated as those with definitive CDI (20 patients for whom data was available) and matched with cases in group 2 (40 patients) and group 3 (40 patients). C. difficile grew from 6% (263/4379) of stool specimens; 14·4% of these had positive EIA, of which 3% were resistant to metronidazole. Three isolates had decreased vancomycin susceptibility. Patients in groups 1 and 2 received more antibiotics (P = 0·03) and had more infectious episodes (P = 0·03) than patients in group 3 prior to diarrhoea. Antibiotic administration for C. difficile did not differ between groups 1 and 2. Mortality was similar in all three groups (10%, 12·5% and 5%, P = 0·49). CDI frequency was low in the University Hospital of Crete and isolates were susceptible to metronidazole and vancomycin.

Combination antibiotic treatment versus monotherapy for multidrug-resistant, extensively drug-resistant, and pandrug-resistant Acinetobacter infections: a systematic review.

Controversy surrounds combination treatment or monotherapy against multidrug-resistant (MDR), extensively drug-resistant (XDR), and pandrug-resistant (PDR) Acinetobacter infections in clinical practice. We searched the PubMed and Scopus databases for studies reporting on the clinical outcomes of patients infected with MDR, XDR, and PDR Acinetobacter spp. with regard to the administered intravenous antibiotic treatment. Twelve studies reporting on 1,040 patients suffering from 1,044 infectious episodes of MDR Acinetobacter spp. were included. The overall mortality between studies varied from 28.6 to 70 %; from 25 to 100 % in the monotherapy arm and from 27 to 57.1 % in the combination arm. Combination treatment was superior to monotherapy in three studies, where carbapenem with ampicillin/sulbactam (mortality 30.8 %, p = 0.012), carbapenem with colistin (mortality 23 %, p = 0.009), and combinations of colistin with rifampicin, sulbactam with aminoglycosides, tigecycline with colistin and rifampicin, and tigecycline with rifampicin and amikacin (mortality 27 %, p < 0.05) were used against MDR Acinetobacter spp. resistant at least to carbapenems. The benefit was not validated in the remaining studies. Clinical success varied from 42.4 to 76.9 % and microbiological eradication varied from 32.7 to 67.3 %. Adverse events referred mainly to polymixins nephrotoxicity that varied from 19 to 50 %. The emergence of resistance was noted with tigecycline regimens in off-label uses in three studies. The available data preclude a firm recommendation with regard to combination treatment or monotherapy. For the time being, combination treatment may be preferred for severely ill patients. We urge for randomized controlled trials examining the optimal treatment of infections due to MDR, XDR, and PDR Acinetobacter spp.

Iron deficiency and susceptibility to infections: evaluation of the clinical evidence.

Iron is a fundamental nutrient for human and microbial life. We sought to examine the association of iron deficiency versus normal iron status with the susceptibility to infections. A systematic search in the PubMed and Scopus databases was performed to identify relevant clinical studies. Six studies (including a total of 1,422 participants) met the inclusion criteria: four prospective cohort (859 participants), one retrospective case-control (115 participants), and one retrospective cohort study (448 participants). Intensive care unit (ICU)-acquired and postoperative infections were more common in patients with iron deficiency than among those with normal iron status in two studies, while no difference was reported in another study. In one study examining pregnant women with normal mean iron values, higher soluble transferrin receptor values independently predicted vaginosis-like microflora. Iron deficiency anemia was an independent predictor of respiratory tract infections in one study, and postoperative urinary tract infections were more common in patients with iron deficiency anemia in another. The limited available evidence suggests that individuals with iron deficiency and those with iron deficiency anemia may be more susceptible to infections than patients with normal iron status. Future studies should elucidate further these findings.

Association between use of air-conditioning or fan and survival of elderly febrile patients: a prospective study.

Elderly individuals are more susceptible to excess summer heat. We sought to examine whether the use of cooling systems (air-conditioning or fan) affected the clinical outcomes of elderly febrile patients. We prospectively followed elderly (≥ 75 years old) febrile patients requesting the medical services of the SOS Doctors (a network of physicians performing house-call visits) from July 10 to August 20, 2011. Patients who used cooling systems ("users") were compared with those who did not ("non-users") regarding mortality, clinical outcome of primary illness (improvement or deterioration), and emergency hospitalization. Prospectively collected data were available for 339 individual elderly febrile patients. "Users" had lower mortality (10 % vs. 19 %, p < 0.05) than "non-users"; no difference was noted on clinical improvement (85 % vs. 76 %, p = 0.11) and emergency hospitalization rates (21 % vs. 30 %, p = 0.16). No difference was noted between users of air-conditioning and fan regarding mortality or clinical improvement, but fan use was associated with more hospitalizations (37 % vs. 19 %, p < 0.05). On multivariate analysis (assessing daily ambient temperature, use of cooling systems, patient age, and living conditions), the sole variable significantly associated with mortality was the non-use of cooling systems [odds ratio (OR): 2.18, 95 % confidence interval (CI): 1.06-4.50]. The use of air-conditioning or fan during hot summer periods appeared to be beneficial for elderly febrile patients living in a large city. Large prospective studies are warranted in order to provide further insight into potential individual and public health initiatives aiming to alleviate the impact of excess summer heat on the health of elderly patients.

Prevalence and treatment of aerobic vaginitis among non-pregnant women: evaluation of the evidence for an underestimated clinical entity.

We sought to evaluate the evidence on the prevalence of aerobic vaginitis (AV) among symptomatic non-pregnant women, as well as the treatment administered for this clinical entity. The PubMed and Scopus databases were systematically searched. Sixteen studies met the inclusion criteria, 11 of which reported on the prevalence of possible AV, two on the prevalence of diagnosed AV, and three on the treatment and outcomes of women with diagnosed AV. The prevalence of diagnosed AV varied from 5 to 10.5 %. Streptococcus spp., Staphylococcus aureus, and coagulase-negative staphylococci were the most commonly identified Gram-positive pathogens among women with possible AV, with prevalences of up to 58.7, 41.7, and 37.4 %, respectively, while Escherichia coli was the most common Gram-negative pathogen identified, with a prevalence of up to 23 % among symptomatic women. Regarding antibiotic treatment for AV, the antibiotic schemes administered, which mainly consisted of suppositories of aminoglycosides, showed good effectiveness without serious adverse events provided by any of the included studies. The currently available data suggest that the prevalence of AV is not negligible, while the prevalence of possible AV is considerable. Well-designed studies comparing the prevalence of aerobic pathogens between symptomatic and asymptomatic women are warranted.