Georgios Petrikkos

Two Cases of Infections Due to Multidrug-Resistant Bacteroides fragilis Group Strains

ABSTRACT Bacteroides fragilis group strains are still considered susceptible to most antimicrobial agents used for the treatment of infections caused by anaerobic organisms. We describe two cases of infections due to isolates simultaneously resistant to clindamycin, tetracycline, cefoxitin, piperacillin-tazobactam, and imipenem and, in one of the two cases, to metronidazole. Such infections, although still rare, do exist and tend to complicate treatment.

Future Directions in Mucormycosis Research

Mucormycosis has emerged as an important opportunistic infection, especially in severely immunosuppressed hosts. The evolving epidemiology, immunopathogenesis, molecular virulence studies, early diagnosis, and pitfalls in designing clinical studies of mucormycosis are discussed in this article.

Prevalence of different HPV types and estimation of prognostic risk factors based on the linear array HPV genotyping test.

The aim of the study was to evaluate the prevalence and risk factors of HPV in a gynecologic population attending outpatient clinics using two new molecular tests. The Amplicor HPV test and the Linear Array (LA) HPV Genotyping test were used for the detection of HPV DNA in 320 women. Multiple logistic regression was used to identify independent prognostic factors of HPV positivity. The agreement between the two methods in terms of their qualitative results was 89.3% (kappa: 0.63). Based on the LA results, the overall prevalence of HPV DNA was 49.1%, 95% confidence interval (95% CI: 43.5%, 54.7%). The prevalence of high‐risk HPV types was 30.3%. The predominant types were HPV‐6 (24.8%) and HPV‐16 (20.4%). Among women with normal cytology, the prevalence of HPV was much higher in those presenting other findings, such as inflammation, than those without other abnormal findings (49.5% vs. 31.5%). On the basis of multivariate analysis, the risk of HPV infection was higher among women with multiple sexual partners [>3 vs. 1: OR = 3.1, 95% CI: (1.5, 7.2)], Pap smear findings [low/high‐grade lesions vs. negative: OR = 2.8, 95% CI: (1.2, 6.5)], the presence of warts [yes vs. no: OR = 3.0, 95% CI: (1.5, 6.3)] and no history of child birth [no vs. yes: OR = 2.6, 95% CI: (1.0, 6.7)]. Younger age was an additional risk factor for HPV infection with carcinogenic genotypes [OR for 1 year increase = 0.93, 95% CI: (0.89, 0.98)]. J. Med. Virol. 81:2059–2065, 2009.

An Unusual Cutaneous Tumor: African Histoplasmosis following Mudbaths: Case Report and Review

African histoplasmosis, caused by Histoplasma capsulatum var. duboisii, is endemic in Africa. The disease usually involves the skin, subcutaneous tissue, and bones. A case of African histoplasmosis presenting as a cutaneous tumor and non-healing wound in a 66-year-old immunocompetent male residing in Africa, the first ever reported following mudbaths and acupuncture, is hereby reported. Diagnosis was confirmed by means of polymerase chain reaction performed on tissue material. The patient was started on long-term itraconazole therapy and he responded well. African histoplasmosis should be included in the differential diagnosis of non-healing wounds or tumor-like lesions, especially in the context of mudbaths in an endemic area.

Risk Factors for Coexistence of Fluoroquinolone Resistance and ESBL Production among Enterobacteriaceae in a Greek University Hospital

Abstract The purpose of this study was to identify risk factors for fluoroquinolone resist-ance (QR) among ESBL-producing Enterobacteriaceae causing nosocomial infections. The study was conducted in Laikon General Hospital in Athens, Greece, during the period January 2004 - January 2005. Epidemiological and clinical data were collected from the medical charts of the patients diagnosed with nosocomial infections due to an ESBL-producing Enterobacteriaceae. QR was 60% among the 84 ESBL-producing Enterobacteriaceae isolates. Infection from QR-ESBL bacteria was associated with increased hospital stay (p=0.028); QR-ESBL bacteria were isolated later during hospitalization than fluoroquinolone suscep-tible (QS)-ESBL (p=0.089); factors associated with QR were immune-deficiency (p=0.047), previous use of carbapenems (p=0.08) and fluoroquinolones (p=0.067), and admission to the Transplantation Unit (p=0.047). In addition, QR-ESBL bacteria were more likely to be resistant to co-trimoxazole (p<0.001), gentamicin (p=0.054) and tobramycin (p=0.004). Logistic regression analysis indicated that admission to the transplantation unit was an independent risk factor for infection due to a QR-ESBL isolate. Results of this study question ciprofloxacins usefulness as a valid alternative to carbapenems in our hospital for the treatment of infections due to ESBL-producing bacteria. In addition strategies for addressing the QR-ESBL situation should focus on limiting fluoroquinolone and carbapenem consumption and emphasize on barrier precautions in patients with longer hospitalization, immunosuppression, or admission to the transplantation unit.

Comparative evaluation of conventional and real-time PCR assays for detecting Bacteroides fragilis in clinical samples

ABSTRACT A conventional PCR and a real-time PCR for detecting Bacteroides fragilis were evaluated against clinical specimens. Analytical sensitivities were 100 and 40 fg of DNA, respectively. Detection limits were 100 and 10 CFU/ml, respectively. A total of six culture-negative specimens were positive by PCR. Altering the gold standard from “positive culture” to “positive culture or both PCR assays positive” resulted in sensitivities of 91.7% and 100%, respectively, and in specificities of 100% and 98.6%, respectively.

Association Between Candiduria and Candidemia: A Clinical and Molecular Analysis of Cases

The risk of developing candidemia after candiduria is reportedly very low, but it has not been adequately investigated. The aim of this study was to examine the molecular relatedness between Candida strains isolated from adult patients with candidemia and concomitant candiduria in association with the clinical characteristics of the cases. All episodes of candidemia occurring in a tertiary care academic hospital during a 5-year period were recorded prospectively. Patients with episodes of candiduria occurring two weeks preceding to or one week following a positive for Candida blood culture were included in the study. The genotypic relatedness of Candida strains isolated from blood and urine was investigated by pulsed-field gel electrophoresis after digestion with the BssHII restriction endonuclease. We recorded 141 candidemia episodes, occurring in 134 patients. Twelve episodes of candidemia with concomitant candiduria occurred in 11 patients (8% of all candidemias). In six of these episodes, the strains in the blood–urine pairs belonged to different species. In two episodes, the isolates belonged to the same species but were not genetically related, and only in four (2.8% of all candidemias), the strains were related. All four patients were severely ill and had multiple risk factors for candidemia. These findings indicate that in hospitalized patients with candidemia, concomitant candiduria is rare and usually an independent event, confirming previous reports. In the critically ill, however, the existence of genetically related strains in blood and urine appears to be more frequent, with more probable the hematogenous dissemination.

B-lymphocyte, Macrophage and Mast Cell Density in the Stroma Underlying HPV-Related Cervical Squamous Epithelial Lesions and their Relationship to Disease Severity: an Immunohistochemical Study

Introduction: B lymphocyte, macrophage and mast cell densities in the stroma underlying cervical low and high grade squamous intraepithelial lesions (LSIL and HSIL) and squamous cell carcinoma (SCC) in 200 tissue samples, with concomitant HPV typing, was assessed, in order to examine their relationship to disease status and progression. Methods: Sections from 215 cervical specimens (149 LSIL, 38 HSIL, 13 SCC and 15 normal cervical mucosae) were immunostained for B lymphocytes (CD20), macrophages (CD68) and mast cells (CD117). The number of cells per high power field (henceforth called density) in the stroma underlying epithelial lesions was assessed. Statistical analysis was performed using four ordinal scale groups of increasing severity (normal, LSIL, HSIL and SCC). Results: Densities of all three cell types had a statistically significant, proportional correlation to disease severity, more so for B lymphocytes. Increased density of any cell type is linked to an increase in the densities of the remaining two. A statistically significant difference in B lymphocyte and mast cell density was found between LSIL and HSIL. No cell type density was found to be predictive of the outcome of LSIL. No relationship with HPV type was found. Discussion: Increased B lymphocyte and mast cell density in the stroma underlying cervical HSIL and SCC compared to LSIL suggests a possible relationship of both cell types to progression of cervical SIL. No predictive value of the density of any cell type was found concerning the outcome of LSIL. Immunohistochemistry may contribute to elucidate the relationship of local immunity effector cells to cervical epithelial lesions.

Complicated Lemierre Syndrome Caused by Streptococcus gordonii and Possible Rickettsial Co-Infection in a Patient with Thrombophilia Predisposition

Aims Lemierre syndrome is a life-threating condition characterized by recent oropharyngeal infection, internal jugular vein thrombosis, and anaerobic septicemia. It is usually caused by Fusobacterium necrophorum. Methods A young Romanian male presented with fever and rigors, mild tachypnea, hypoxia, sore throat, decayed teeth, and tenderness of the left carotid triangle. Laboratory examination indicated severe sepsis with disseminated intravascular coagulation, acute renal failure, and acute respiratory distress syndrome while the Doppler ultrasonography of the carotids revealed left internal jugular venous thrombosis. The patient was administered piperacillin/tazobactam and vancomycin intravenously, doxycycline orally, and anti-coagulation by enoxaparin based on the diagnosis of Lemierre syndrome. Meanwhile, he was complicated by bilateral diffuse pulmonary cavities and encapsulated pleural effusions and so transcutaneous drainage was performed. The patient was discharged after a month and continued his treatment with oral phenoxypenicillin and doxycycline until full radiographic improvement. He was switched to oral anti-coagulation by vitamin-K antagonists and was referred to a hematologist, a vascular-surgeon, and a dentist. Results Streptococcus gordonii was isolated from the patient’s blood and pleural fluid cultures and serology for Rickettsial spp. IgM was positive. Thrombophilia genetic tests revealed three minor mutations for fibrinogen-455, plasminogen activator inhibitor-1, and methylenetetrahydrofolate reductase. According to the literature, S. gordonii is not usually a causative agent and Rickettsial spp. have as yet not been correlated with Lemierre syndrome. The failure of left jugular vein recanalization shows a possible causative role of the underlying thrombophilic predisposition. Discussion Because of the syndrome’s rarity and the atypical microorganisms isolated in this case, increased awareness is advised for its diagnosis and the underlying mechanisms involved in its genesis. The role of anti-coagulation is debatable. LEARNING POINTS Very rare condition. Medical practitioners should be vigilant in its diagnosis since septic jugular vein thrombophlebitis could be misdiagnosed as neck lymphadenitis. Duration of antibiotic therapy and additional anticoagulation treatment are still under discussion. Underlying thrombophilia predisposition should be excluded.

High prevalence of the UGT1A1*28 variant in HIV-infected individuals in Greece

7‐11 November 2010, Tenth International Congress on Drug Therapy in HIV Infection, Glasgow, UK