Boaz Avidor

Bartonella koehlerae, a New Cat-Associated Agent of Culture-Negative Human Endocarditis

ABSTRACT Bartonella koehlerae is reported for the first time to be a human pathogen that causes culture-negative endocarditis. It is also shown that this species, isolated twice before from domestic cats, can be recovered as well from a stray cat population in Israel. This work follows a recent report of the same case in which the causative agent was misidentified as B. henselae, based on serology and PCR-restriction fragment length polymorphism (RFLP) analysis (A. Schattner, O. Zimhony, B. Avidor, and M. Gilad, Lancet 361:1786, 2003). B. koehlerae was identified in the valvular tissue of an endocarditis patient by DNA sequencing of the PCR products of two Bartonella genes: the genes for citrate synthase (gltA) and riboflavin synthase (ribC). The commonly used PCR-RFLP analysis of the TaqI-digested gltA PCR product did not distinguish between B. koehlerae and B. quintana or between B. elizabethae and B. clarridgeiae. PmlI digestion of the gltA amplification product failed to differentiate between B. quintana, B. clarridgeiae, and B. elizabethae. RFLP analysis of the heat shock protein (htrA) gene by TaqI digestion misidentified B. koehlerae as B. henselae. However, RFLP analysis of the ribC PCR product, digested with TaqI, was able to distinguish between the human endocarditis-associated Bartonella species tested, B. henselae, B. quintana, B. elizabethae, and B. koehlerae, as well as between the cat-associated Bartonella species, B. henselae and B. clarridgeiae. Given the expanding number of Bartonella species emerging as human pathogens, it is suggested that PCR-RFLP analysis for the diagnosis of Bartonella infections target several genes and be coupled with DNA sequencing to avoid species identification.

Long-Term Serological Analysis and Clinical Follow-Up of Patients with Cat Scratch Disease

A highly specific enzyme immunoassay (EIA) was recently described for use in the diagnosis of cat scratch disease (CSD). However, data regarding EIA antibody kinetics or its correlation with long-term clinical follow-up data are lacking. The association between antibody kinetics, clinical spectrum, and disease duration were studied in 98 patients with CSD. The median duration of follow-up was 35.3 weeks (range, 2-211.3 weeks). Results of EIA testing for detection of anti-Bartonella henselae immunoglobulin M (IgM) antibodies (detected in 53% of the patients) remained positive for < or =3 months. Therefore, the presence of IgM indicated acute infection. Titers of immunoglobulin G (IgG) also decreased over time; 25% of the patients remained seropositive for >1 year after the onset of CSD. Onset of CSD in patients with an IgG titer with an optical density of > or =1.0 occurred within the prior 12 months. No association was found between antibody titers or their kinetics and the clinical manifestations or duration of disease. EIA allows for the identification of atypical manifestations of CSD that were unrecognized before the use of serological assays. Complete recovery from these manifestations may take months. Results of this study provide additional data supporting the utility of EIA in the serodiagnosis of CSD.

Musculoskeletal Manifestations of Cat Scratch Disease

BACKGROUND Musculoskeletal manifestations (MMs) are considered to be rare in cat scratch disease (CSD) and are not well characterized. We aimed to study MMs of CSD. METHODS A surveillance study performed over 11 years identified patients with CSD on the basis of compatible clinical presentation and confirmatory serological test or PCR results for Bartonella henselae. Patients with CSD who had MMs (i.e., myalgia, arthritis, arthralgia, tendinitis, osteomyelitis, and neuralgia) were compared with patients with CSD who did not have MMs (control subjects). RESULTS Of 913 patients with CSD, 96 (10.5%) had MMs. Myalgia (in 53 patients [5.8%]) was often severe, with a median duration of 4 weeks (range, 1-26 weeks). Arthropathy (arthralgia and/or arthritis; in 50 patients [5.5%]) occurred mainly in the medium and large joints and was classified as moderate or severe in 26 patients, with a median duration of 5.5 weeks (range, 1-240 weeks). In 7 patients, symptoms persisted for >or=1 year; 5 developed chronic disease. Tendinitis, neuralgia, and osteomyelitis occurred in 7, 4, and 2 patients, respectively. Patients with MMs were significantly older than patients in the control group (median age, 31.5 years vs. 15.0 years). In multivariate analysis, age >20 years was associated with having any MM (relative risk [RR], 4.96; 95% confidence interval [CI], 2.79-8.8), myalgia (RR, 4.69; 95% CI, 2.22-9.88), and arthropathy (RR, 11.0; 95% CI, 4.3-28.2). Arthropathy was also associated with female sex (RR, 1.89; 95% CI, 1.01-3.52) and erythema nodosum (RR, 4.07; 95% CI, 1.38-12.02). CONCLUSIONS MMs of CSD are more common than previously thought and affect one-tenth of patients with CSD. MMs occur mostly in patients aged >20 years and may be severe and prolonged. Osteomyelitis, the most well known MM of CSD is, in fact, the rarest.

Enzyme Immunoassay for the Diagnosis of Cat-Scratch Disease Defined by Polymerase Chain Reaction

Whole-cell immunofluorescent antibody (IFA) tests for detection of anti-Bartonella henselae immunoglobulin (Ig) G are commonly used to diagnose cat-scratch disease (CSD). The need to cultivate B. henselae in Vero cells for antigen preparation and the absence of routinely applied IFA assays for IgM constitute the major disadvantages of this form of test. We describe the results of an enzyme immunoassay (EIA) for IgM and IgG that used N-lauroyl-sarcosine-insoluble outer membrane antigens from agar-grown B. henselae performed in 84 patients with definite CSD (regional lymphadenitis, cat contact, and > or =1 confirmatory test: polymerase chain reaction, skin test, or B. henselae culture). Although this method has been used as a diagnostic tool in several case reports, it has not previously been evaluated in a large study of definitively proven CSD cases. Results of this study indicate that the EIA described herein can play an important role in the serodiagnosis of CSD, although improvement of the sensitivity, particularly that of the IgM, would be desirable.

DNA Amplification for the Diagnosis of Cat-Scratch Disease in Small-Quantity Clinical Specimens

Diagnosis of cat-scratch disease (CSD) by polymerase chain reaction (PCR) of lymph node fineneedle aspiration (FNA) and primary lesion specimens can be difficult owing to the minute amount of available material. A PCR assay specifically suited to test these specimens was developed. First, small-quantity (10 microL) samples were prepared from 17 CSD-positive and 16 CSD-negative specimens, and DNA extraction and amplification from these samples were compared using 3 methods. Sensitivity and specificity of PCR were 100% using material collected on glass microscope slides and by using Qiagen (Hilden, Germany) columns for DNA extraction. Then, this method was used to test 11 archival glass microscope slides of FNA (7 malignant neoplasms, 4 undiagnosed lymphadenitis) and 2 primary lesion specimens. Two of the 4 lymphadenitis samples and the 2 primary lesion specimens were PCR positive. The technique presented could facilitate CSD diagnosis from a wider range of clinical samples.

Detection of Bartonella spp. in wild rodents in Israel using HRM real-time PCR

The prevalence of Bartonella spp. in wild rodents was studied in 19 geographical locations in Israel. One hundred and twelve rodents belonging to five species (Mus musculus, Rattus rattus, Microtus socialis, Acomys cahirinus and Apodemus sylvaticus) were included in the survey. In addition, 156 ectoparasites were collected from the rodents. Spleen sample from each rodent and the ectoparasites were examined for the presence of Bartonella DNA using high resolution melt (HRM) real-time PCR. The method was designed for the simultaneous detection and differentiation of eight Bartonella spp. according to the nucleotide variation in each of two gene fragments (rpoB and gltA) and the 16S-23S intergenic spacer (ITS) locus, using the same PCR protocol which allowed the simultaneous amplification of the three different loci. Bartonella DNA was detected in spleen samples of 19 out of 79 (24%) black rats (R. rattus) and in 1 of 4 (25%) Cairo spiny mice (A. cahirinus). In addition, 15 of 34 (44%) flea pools harbored Bartonella DNA. Only rat flea (Xenopsyla cheopis) pools collected from black rats (R. rattus) were positive for Bartonella DNA. The Bartonella sp. detected in spleen samples from black rats (R. rattus) was closely related to both B. tribocorum and B. elizabethae. The species detected in the Cairo spiny mouse (A. cahirinus) spleen sample was closely related to the zoonotic pathogen, B. elizabethae. These results indicate that Bartonella species are highly prevalent in suburban rodent populations and their ectoparasites in Israel. Further investigation of the prevalence and zoonotic potential of the Bartonella species detected in the black rats and the Cairo spiny mouse is warranted.

Incidence of cytomegalovirus-associated thrombosis and its risk factors: a case-control study.

INTRODUCTION Cytomegalovirus (CMV)-associated thrombosis has been reported sporadically in the medical literature until now. However, thrombosis incidence and its risk factors have never been studied in a cohort of patients with acute CMV infection. MATERIALS AND METHODS A retrospective case-control study. Medical charts and imaging study reports of all consecutive patients diagnosed with acute CMV infection during the years 2005-2006 in a tertiary medical center were reviewed for the presence of arterial and/or venous thromboses, and their acquired as well as inherited predispositions. The control group included age-matched and sex-matched consecutive patients, in whom acute CMV infection was excluded. Laboratory tests used for acute CMV infection diagnosis/exclusion were also matched, including serology, antigenemia, and PCR. RESULTS Included were 140 patients with acute CMV infection (study group) and 140 consecutive matched patients in whom acute CMV infection was excluded (control group). Among the control group, none of the patients had thrombosis, while among the study group, nine (6.4%; p=0.003) patients had thrombosis: five (3.6%; p=0.025) patients had arterial thrombosis and four (2.9%; p=0.045) patients had venous thrombosis. Binary logistic regression analysis showed that acute CMV infection was independently associated with thrombosis among the whole cohort (p=0.004), while use of oral contraceptives/hormones or pregnancy were independently associated with thrombosis among patients with acute CMV infection (p=0.043). CONCLUSIONS Thrombosis in patients with acute CMV infection is not rare. Acute CMV infection is associated with thrombosis independent of other risk factors for thrombosis. We hope to raise physicians awareness to the association between acute CMV infection and thrombosis.

Pilot Study of Prevalence of High-Risk Human Papillomavirus Genotypes in Israeli Jewish Women Referred for Colposcopic Examination

ABSTRACT The objective of the present study was to determine the prevalence of high-risk (HR) human papillomavirus (HPV) genotypes in a group of Israeli Jewish women referred for colposcopic examination. Scrape specimens were prospectively collected from 84 women referred for colposcopic examination. All the women underwent Papanicolaou (Pap) smears and colposcopies, and some also underwent cervical or loop electrosurgical excision procedure biopsy. HR HPV was detected in scrape specimens (Amplicor HPV test; Roche Molecular Systems), and the individual genotypes in these specimens were identified (HPV GenoArray test kit; Hybribio Ltd., Hong Kong). Forty-one (49%) specimens were positive by the Amplicor HPV test. Sixty-four samples (41 positive and 23 negative by the Amplicor HPV test) were also assayed by use of the HPV GenoArray kit. The overall level of agreement between the two assays was 93.8% (Cohens kappa = 0.98). HR genotypes were found in 37/41 (90%) HPV-positive samples. The prevalences of the HR HPV genotypes in the 37 HPV-positive samples were 41% of patients for HPV type 16 (HPV-16), 22% for HPV-39, 19% for HPV-52, and 14% for HPV-18. Forty-one percent of these patients were infected with a single HR genotype, whereas 59% were infected with mixtures of HR genotypes. The presence of a relatively high percentage of HPV types 39 and 52 and the relatively high incidence of infections with mixtures of genotypes may be one of the reasons for the low rate of conversion from high-grade squamous intraepithelial lesions to invasive carcinoma in Israeli women. Larger and more comprehensive studies are warranted to investigate this issue in greater detail.

Evaluation of a Benchtop HIV Ultradeep Pyrosequencing Drug Resistance Assay in the Clinical Laboratory

ABSTRACT Detection of low-abundance drug resistance mutations (DRMs) of HIV-1 is an evolving approach in clinical practice. Ultradeep pyrosequencing has shown to be effective in detecting such mutations. The lack of a standardized commercially based assay limits the wide use of this method in clinical settings. 454 Life Sciences (Roche) is developing an HIV ultradeep pyrosequencing assay for their benchtop sequencer. We assessed the prototype plate in the clinical laboratory. Plasma samples genotyped by the standardized TruGene kit were retrospectively tested by this assay. Drug-treated subjects failing therapy and drug-naive patients were included. DRM analysis was based on the International AIDS Society USA DRM list and the Stanford algorithm. The prototype assay detected all of the DRMs detected by TruGene and additional 50 low-abundance DRMs. Several patients had low-abundance D67N, K70R, and M184V reverse transcriptase inhibitor mutations that persisted long after discontinuation of the drug that elicited these mutations. Additional patient harbored low-abundance V32I major protease inhibitor mutation, which under darunavir selection evolved later to be detected by TruGene. Stanford analysis suggested that some of the low-abundance DRMs were likely to affect the resistance burden in these subjects. The prototype assay performs at least as well as TruGene and has the advantage of detecting low-abundance drug resistance mutations undetected by TruGene. Its ease of use and lab-scale platform will likely facilitate its use in the clinical laboratory. The extent to which the detection of low-abundance DRMs will affect patient management is still unknown, but it is hoped that use of such an assay in clinical practice will help resolve this important question.

Isolated Splenic Cat Scratch Disease in an Immunocompetent Adult Woman

We report a case of isolated splenic cat scratch disease in an immunocompetent woman. The clinical presentation of prolonged fever, night sweats, weakness, and intrasplenic lesions was highly suggestive of lymphoma. This is the second reported case of isolated splenic cat scratch disease in an adult and the first in a healthy adult.