Risk factors of severe blastomycosis and comparison of diagnosis and outcomes between immunocompetent and immunocompromised patients.

BACKGROUND: Blastomycosis is an endemic fungal infection that causes pulmonary and systemic disease. It can occur irrespective of the patient's immune status. The risk factors associated with the severity of the disease are not well studied. METHODS: This is a retrospective study of patients admitted with blastomycosis at the University of Kentucky Hospital from 2004 to 2019. Logistic regression was used to identify variables associated with severe blastomycosis. RESULTS: A total of 76 patients were identified; 22 (28.9%) had at least one immunosuppressive condition. Pulmonary blastomycosis was reported in 49/76 (65%) of the patients and disseminated infection in 27/76 (35.5%). All diagnostic tests were not significantly different in diagnostic results in immunocompromised vs immunocompetent patients. Cultures and histopathology were positive in 56/61 (91.8%) and 54/63 (85.7%) respectively. Blastomyces or Histoplasma antigen test was positive in 13/17 (76.4%) in immunocompromised patients compared to 26/42 (61.9%) in immunocompetent patients. Immunocompromised patients were more likely to be admitted to the hospital and ICU compared to immunocompetent patients. In the multivariate analysis, pulmonary multilobar disease (RR 5.68; 95% CI 2.13-15.15), obesity (RR 2.39; 95% CI 1.26-4.51), diabetes mellitus (RR 3.50; 95% CI 1.38-8.90) and immunosuppression (RR 2.28; 95% CI 1.14-4.56) were significant independent risk factors for severe blastomycosis. Inpatient mortality proportion was higher in immunocompromised patients but not statistically significant. CONCLUSION: Pulmonary multilobar disease, obesity, diabetes mellitus and immunosuppression were risk factors associated with severe blastomycosis. Immunocompromised patients required more frequent hospitalisations compared to immunocompetent patients.

Changing demographics and risk factors for cryptococcosis: A 12-year review at a tertiary care centre.

BACKGROUND: Cryptococcosis is classically associated with the immunocompromised patients but there is a rising appreciation for its impact on the immunocompetent hosts. We sought to analyse the trends, diagnosis, treatment of different hosts and the effect of immunodeficiency and chronic liver disease on relapse and in-house mortality. METHODS: This is a retrospective study of 12 years of patients with cryptococcosis, divided into three different groups: HIV-infected, transplant and non-HIV non-transplant (NHNT). Data were analysed with Chi-square, unpaired parametric t test, simple and multivariate logistic regression analysis. RESULTS: Of 114 identified patients, 23 (20.2%) had HIV infection, 11 (9.6%) had transplant, 80 (70.2%) were NHNT patients. Overall, mortality was 28.1% (32/114) and relapse occurred in 10.5% (12/114) of patients. The mortality trend was higher (OR = 2.346, p = .287) in the transplant group (45.5%, 5/11) than in HIV (26.1%, 6/23) and NHNT groups (26.3%, 21/80). HIV was associated with relapse; 30.4% (7/23) for HIV-positive patients and 5.5% (5/91) for HIV-negative patients (OR = 7.525, p = .002). Chronic liver disease had a large and statistically significant association with mortality on multivariate analysis (OR = 3.583, p = .013) which was more pronounced than the HIV or transplant groups. It was independently associated with mortality by chi-square analysis (OR 3.137, p = .012). CONCLUSION: Chronic liver disease represented 30.7% (35/114) of all studied patients. It was a risk factor for in-hospital mortality. HIV infection and transplant were not statistically significant for mortality. Relapse was highest in the HIV-infected patients at 30.4% (7/23). These data highlight the effect of type and degree of immunocompromise on cryptococcosis.

Lemierre syndrome.

Lemierre's syndrome is an uncommon complication of pharyngitis in the United States and caused most commonly by the bacterium Fusobacterium necrophorum. The syndrome is characterized by a history of recent pharyngitis followed by ipsilateral internal jugular vein thrombosis and metastatic pulmonary abscesses and is a disease for which patients will seek medical care and advice. As most patients are admitted to the hospital under internal medicine, practitioners should be familiar with the usual signs and symptoms of Lemierre's syndrome along with its diagnosis and treatment. Controversy involves the choice and duration of antimicrobial therapy used for treatment and anticoagulation therapy for internal jugular vein thrombosis. As the diagnosis and management of this syndrome has generated controversy, an updated review of the literature and treatment recommendations may be helpful for providing optimal care for patients with this often unrecognized and confusing infection.

A multicenter evaluation of tests for diagnosis of histoplasmosis.

BACKGROUND: The sensitivity of the MVista Histoplasma antigen enzyme immunoassay (MiraVista Diagnostics) has been evaluated in disseminated histoplasmosis in patients with AIDS and in the "epidemic" form of acute pneumonia. Moreover, there has been no evaluation of the sensitivity of antigenemia detection in disseminated histoplasmosis after the implementation of methods to dissociate immune complexes and denature released antibodies. The goal of this study was to determine the sensitivity of the current antigen assay in different categories of histoplasmosis. METHODS: Urine and serum specimens obtained from 218 patients with histoplasmosis and 229 control subjects, including 30 with blastomycosis, were tested. RESULTS: Antigenuria was detected in 91.8% of 158 patients with disseminated histoplasmosis, 83.3% of 6 patients with acute histoplasmosis, 30.4% of 46 patients with subacute histoplasmosis, and 87.5% of 8 patients with chronic pulmonary histoplasmosis; antigenemia was present in 100% of 31 tested cases of disseminated histoplasmosis. Among patients with disseminated cases, antigenuria was detected more often and at higher concentrations in immunocompromised patients and those with severe disease. Specificity was 99.0% for patients with nonfungal infections (n = 130) and in healthy subjects (n = 69), but cross-reactivity occurred in 90% of patients with blastomycosis. CONCLUSIONS: The sensitivity of antigen detection in disseminated histoplasmosis is higher in immunocompromised patients than in immunocompetent patients and in patients with more severe illness. The sensitivity for detection of antigenemia is similar to that for antigenuria in disseminated infection.

Fatal rhizopus pneumonia in allogeneic stem cell transplant patients despite posaconazole prophylaxis: two cases and review of the literature.

Posaconazole is a triazole with broad spectrum of activity against multiple fungi including members of the fungal order Mucorales. This activity has been shown both in clinical and in vitro studies, which are critically reviewed here. It has become very popular in prophylaxis in acute myelogenous leukemia (AML) induction and in the graft-versus-host disease (GVHD) settings after 2 recent prospective trials that showed advantage of posaconazole prophylaxis compared to fluconazole or itraconazole. In this report, 2 patients are presented, in whom, despite posaconazole prophylaxis, invasive and ultimately fatal Rhizopus pulmonary infections developed. These cases are similar to a previously reported case of Rhizopus infection in a stem cell transplant recipient who also received posaconazole, indicating a potential newly recognized pattern of breakthrough infections in patients receiving posaconazole prophylaxis.

Evaluation of the BD Phoenix automated system for determining antimicrobial susceptibility against carbapenem-resistant Enterobacteriaceae compared with broth microdilution.

PURPOSE: Carbapenem-resistant Enterobacteriaceae (CRE) are increasingly widespread in the healthcare system, resulting in infections associated with mortality of up to 50%. Many laboratories use automated systems to identify CRE isolates and determine susceptibility. The aim of this study was to evaluate categorical agreement between the BD Phoenix automated system and the gold standard - broth microdilution - in determining minimum inhibitory concentrations of CRE. METHODOLOGY: The activity of amikacin, aztreonam, cefepime, ceftazidime, ertapenem, gentamicin, levofloxacin, meropenem, nitrofurantoin, piperacillin-tazobactam and tobramycin on 125 CRE isolates collected from an academic medical centre was evaluated. Categorical agreement between BD Phoenix and broth microdilution was determined, as well as minor error rates, major error rates and very major error rates. RESULTS: BD Phoenix significantly overestimates susceptibility of CRE isolates to amikacin, aztreonam, cefepime, ceftazidime, gentamicin, levofloxacin, meropenem, nitrofurantoin and tobramycin compared with broth microdilution. Overall, categorical agreement of 76% between testing methods indicates the potential diminished ability of BD Phoenix to predict resistance accurately in highly drug-resistant isolates. All tested antimicrobials had higher major error rates compared with previous literature. CONCLUSIONS: BD Phoenix has diminished ability to determine susceptibility of CRE isolates. Further studies are warranted in order to validate BD Phoenix susceptibility testing in highly resistant CRE isolates. The mechanism by which isolates are resistant to carbapenems does not impact the ability of BD Phoenix to determine susceptibility.

Invasive enteric infections in hospitalized patients with underlying strongyloidiasis.

Disseminated strongyloidiasis is often associated with enteric bacterial infections. This study was undertaken to determine if enteric organisms caused extraintestinal infections in patients infected with Strongyloides stercoralis but without apparent dissemination. The medical records of hospitalized patients from central Kentucky with strongyloidiasis (1993-2003) were examined to determine the occurrence of extraintestinal infections with enteric organisms. Of 30 patients with S stercoralis, 16 had invasive infections, including sepsis, meningitis, pneumonia, peritonitis, and endocarditis caused by enteric bacteria and Candida organisms. Infections were seen in 8 (62%) of 13 patients with disseminated strongyloidiasis and 8 (47%) of 17 with disease apparently limited to the gastrointestinal tract. Fifteen patients were receiving corticosteroids or other immunosuppressive therapy. Peripheral eosinophilia was seen in only 23% (7/30). Infection with S stercoralis, even without obvious dissemination, may predispose to invasive infections caused by enteric organisms. In Strongyloides-endemic areas, patients with invasive infections caused by enteric organisms should be examined for coinfection with S stercoralis.

Differences in Rhodococcus equi Infections Based on Immune Status and Antibiotic Susceptibility of Clinical Isolates in a Case Series of 12 Patients and Cases in the Literature.

Rhodococcus equi is an unusual zoonotic pathogen that can cause life-threatening diseases in susceptible hosts. Twelve patients with R. equi infection in Kentucky were compared to 137 cases reported in the literature. Although lungs were the primary sites of infection in immunocompromised patients, extrapulmonary involvement only was more common in immunocompetent patients (P < 0.0001). Mortality in R. equi-infected HIV patients was lower in the HAART era (8%) than in pre-HAART era (56%) (P < 0.0001), suggesting that HAART improves prognosis in these patients. Most (85-100%) of clinical isolates were susceptible to vancomycin, clarithromycin, rifampin, aminoglycosides, ciprofloxacin, and imipenem. Interestingly, there was a marked difference in susceptibility of the isolates to cotrimoxazole between Europe (35/76) and the US (15/15) (P < 0.0001). Empiric treatment of R. equi infection should include a combination of two antibiotics, preferably selected from vancomycin, imipenem, clarithromycin/azithromycin, ciprofloxacin, rifampin, or cotrimoxazole. Local antibiograms should be checked prior to using cotrimoxazole due to developing resistance.

Mycobacterium marinum Infection After Exposure to Coal Mine Water.

Mycobacterium marinum infection has been historically associated with exposure to aquariums, swimming pools, fish, or other marine fauna. We present a case of M marinum left wrist tenosynovitis and elbow bursitis associated with a puncture injury and exposure to coal mine water in Illinois.

Why is the microbiology lab calling about an extended-spectrum beta-lactamase bacterium from a wound culture?

As more and more gram-negative bacteria produce extended-spectrum beta-lactamases, it is important that physicians know what to do when these bacteria cause postoperative infections in patients.

Post operative fungal endopthalmitis due to Geotrichum candidum.

Geotrichum species have been rarely reported as the cause of sepsis, disseminated infection in immunosuppressed patients. The patient we describe developed indolent endophthalmitis four months after her routine right eye cataract surgery. The intraoperative sample from right vitreous fluid grew Geotrichum candidum. The patient underwent vitrectomy, artificial lens explantation and intravitreal injection of amphotericin B followed by oral voriconazole. Despite these interventions, she underwent enucleation. This is the first published case of Geotrichum candidum endophthalmitis.

Empyema caused by trichomonas.

Empyema is one of the potential complications of lower respiratory tract infections. Very rarely, in predisposed individuals, empyema can be caused by Trichomonas species, of which Trichomonas tenax appears to be the most common cause. Here, we present a case of trichomonal empyema in a 56-year-old man and review the available literature of this rare occurrence.

Point prevalence of Cryptosporidium, Cyclospora, and Isospora infections in patients being evaluated for diarrhea.

From March to September 2001, 315 specimens from "nonrepeat" patients that were submitted for ova and parasite examination were stained using the Kinyoun modified acid-fast stain to detect the intestinal coccidians. Four patients (1.3%) were infected with coccidians, 2 with Cryptosporidium parvum and 2 with Cyclospora cayetanensis. No infections with Isospora belli were detected. In comparison, 15 patients (4.8%) had infections with one or more intestinal parasites detected by routine trichrome staining: 5 had Giardia lamblia; 2, Dientamoeba fragilis; 3, Strongyloides stercoralis; 1, Iodamoeba bütschlii; 3, Endolimax nana; 6, Blastocystis hominis; and 1, Entamoeba coli. Four patients were multiply infected. Coccidians made up 29% of the clinically significant parasitic infections. The coccidians were missed in all 4 cases because no special staining was ordered. Clinicians need to be reminded that additional tests should be ordered to fully evaluate patients with chronic diarrhea in which no diagnosis is found by routine testing.

Mycobacterium mucogenicum isolated from a patient with granulomatous hepatitis.

Mycobacterium mucogenicum is a recently characterized, rapid-growing mycobacteria rarely seen in human infections. We describe the case of a 51-year-old man with rapidly progressive granulomatous hepatitis caused by M. mucogenicum. Although premortem evaluation failed to identify an etiologic agent, autopsy liver cultures produced smooth, rapid-growing mycobacterial colonies. Biochemical, growth, and cell wall fatty acid characteristics were consistent with the identification of M. mucogenicum.

Biofilm formation on tracheostomy tubes.

An increased awareness of biofilms and their mechanisms has led to a better understanding of bacterial infections that occur following the placement of tracheostomy tubes and other implanted devices and prostheses. One aspect of biofilm formation that is still subject to debate is whether the specific material that is used to manufacture a tube has any bearing in the incidence of infection. We conducted a test of four different tube materials--polyvinyl chloride, silicone, stainless steel, and sterling silver--to ascertain how bacterial biofilms form on tracheostomy tubes and to determine if there is a material-dependent difference in biofilm formation. Scanning electron microscopy demonstrated that Pseudomonas aeruginosa and Staphylococcus epidermidis both formed bacterial biofilms on tracheostomy tubes in vitro. We also found that there was no difference in susceptibility to biofilm formation among the four tube materials tested.