Molecular Diagnosis of Cat Scratch Disease: a 25-Year Retrospective Comparative Analysis of Various Clinical Specimens and Different PCR Assays.

Cat-scratch disease (CSD), caused primarily by Bartonella henselae, is a common etiology of infectious regional lymphadenopathy. Lymphadenopathy is preceded by a primary inoculation lesion and may progress to suppuration. Laboratory diagnosis of CSD is hampered by the limitations of available confirmatory tests. PCR, in general, is highly sensitive and specific; however, clinical sensitivity in CSD varies greatly between studies. We aimed to identify clinical specimens and PCR assays best suited for CSD diagnosis using a national CSD registry and a uniform case definition. Different clinical specimens and PCR assays, including conventional and real-time PCR, were evaluated. PCR was positive in 335/390 (86%) CSD patients and 425/482 (88%) PCR tests. The highest PCR sensitivity was achieved in lymph node pus aspirates (96%; n = 278 tests) followed by primary lesions (88%; n = 50), lymph node fine needle aspirations (85%; n = 46), lymph node biopsy specimens (73%; n = 91) and paraffin-embedded lymph nodes (59%; n = 17), (P < 0.001). Sensitivity was similar in all types of PCR assays studied. PCR negative predictive value of pus aspirate and lymph node biopsy specimen patient groups was 82% and 72%, respectively. Specificity was 100% based on 125 non-CSD patients with negative PCR. In conclusion, the specimen type rather than the PCR assay type has a major impact on CSD molecular diagnosis. We assume that the inadequate sensitivity of the biopsy specimens was due to sampling errors or the presence of inhibitory factors. Primary lesions should be sampled more frequently for CSD diagnosis. Physicians should be aware of the low PCR negative predictive value of lymph node biopsy specimens. IMPORTANCE Polymerase chain reaction (PCR) for the detection of Bartonella henselae is an important tool for the diagnosis of cat scratch disease (CSD); however, clinical sensitivity varies greatly between studies. The current study shows that the specimen type, with pus aspiration, fine needle aspiration, and primary inoculation lesion having significantly higher sensitivity than fresh or formalin-fixed paraffin-embedded lymph node biopsy specimen, rather than the type of the PCR assay, whether a conventional or a real-time assay, has a major impact on the performance of diagnostic PCR for CSD. The new data provide new tools for the clinical microbiologist when interpreting the results of the PCR assays. Primary inoculation lesions, although easily accessible, are often neglected and should be sampled more frequently for molecular diagnosis of CSD. Physicians should be aware that negative PCR, particularly if performed on fresh or paraffin-embedded lymph node biopsy specimens, does not exclude CSD.

Laboratory Diagnosis of 37 Cases of Bartonella Endocarditis Based on Enzyme Immunoassay and Real-Time PCR.

Bartonella spp., mostly Bartonella quintana and B. henselae, are a common cause of culture-negative endocarditis. Serology using immunofluorescence assay (IFA) and PCR performed on cardiac tissues are the mainstays of diagnosis. We developed an enzyme immunoassay (EIA) and a novel multiplex real-time PCR assay, utilizing Bartonella genus-specific, B. henselae-specific, and B. quintana-specific SimpleProbe probes, for diagnosis of Bartonella endocarditis. We aimed to evaluate the performance of these assays. Thirty-seven patients with definite endocarditis, 18 with B. henselae, 18 with B. quintana, and 1 with B. koehlerae, were studied. Diagnosis was confirmed by conventional PCR and DNA sequencing of surgical cardiac specimens. Similar to the case with IFA, anti-Bartonella IgG titers of ≥1:800 were found in 94% of patients by EIA; cross-reactivity between B. henselae and B. quintana precluded species-specific serodiagnosis, and frequent (41%) but low-titer cross-reactivity between Coxiella burnetii antibodies and B. henselae antigen was found in patients with Q fever endocarditis. Low-titer (1:100) cross-reactivity was uncommonly found also in patients with brucellosis and culture-positive endocarditis, particularly Enterococcus faecalis endocarditis. Real-time PCR performed on explanted heart valves/vegetations was in complete agreement with results of sequence-based diagnosis with characteristic melting curves. The genus-specific probe identified five additional endocarditis-associated Bartonella spp. at the genus level. In conclusion, EIA coupled with a novel real-time PCR assay can play an important role in Bartonella endocarditis diagnosis and expand the diagnostic arsenal at the disposal of the clinical microbiologist. Since serology remains a major diagnostic tool, recognizing its pitfalls is essential to avoid incorrect diagnosis.

Cat Scratch Disease Presenting as Fever of Unknown Origin Is a Unique Clinical Syndrome.

BACKGROUND: Fever of unknown origin (FUO) is a rare manifestation of cat scratch disease (CSD). Data regarding CSD-associated FUO (CSD-FUO), particularly in adults, are limited. We aimed to study disease manifestations and long-term clinical outcome. METHODS: A national CSD surveillance study has been conducted in Israel since 1991. Data are obtained using questionnaires, review of medical records, and telephone interviews. FUO was defined as fever of ≥14 days without an identifiable cause. CSD-FUO patients were identified in the 2004-2017 CSD national registry. Follow-up included outpatient clinic visits and telephone/e-mail surveys. RESULTS: The study included 66 CSD-FUO patients. Median age was 35.5 years (range, 3-88). Median fever duration was 4 weeks (range, 2-9). Relapsing fever pattern was reported in 52% of patients, weight loss in 57%, and night sweats in 48%. Involvement of ≥1 organs occurred in 59% of patients; hepatosplenic space-occupying lesions (35%), abdominal/mediastinal lymphadenopathy (20%), ocular disease (18%), and multifocal osteomyelitis (6%) were the most common. Malignancy, particularly lymphoma, was the initial radiological interpretation in 21% of patients; 32% underwent invasive diagnostic procedures. Of the 59 patients available for follow-up (median duration, 31 weeks; range, 4-445), 95% had complete recovery; 3 patients remained with ocular sequelae. CONCLUSION: This is the first attempt to characterize CSD-FUO as a unique syndrome that may be severe and debilitating and often mimics malignancy. Relapsing fever is a common clinical phenotype. Multiorgan involvement is common. Recovery was complete in all patients except in those with ocular disease.

Orbital complications associated with paranasal sinus infections - A 10-year experience in Israel.

OBJECTIVE: Orbital involvement is the most common complication of sinus infections. The epidemiology of the disease is continuously changing in the antibiotic era. MATERIALS AND METHODS: Data on patients who were hospitalized due to acute sinusitis and orbital complications were retrospectively collected and analyzed from four medical centers in Israel during the years 2002-2012. RESULTS: 288 patients were included in the study, the average age was 14.4 years, 180 were males, and 220 were children. No significant annual increase in the number of patients was noted. The lowest number of patients was found during the summer 19.4%. A linear direct correlation was found between older age and prolonged hospital stay. Children were presented with a significantly higher Chandler score than adults. No patient had cavernous sinus thrombosis. 101 (35%) patients received antibiotics before hospital admission. Their average hospital stay was similar to those who were not treated prior to admission. 106 patients (39.8%) had fever. A direct correlation was found between older age and the presence of fever. 102 (35.4%) patients had leukocytosis. The difference in white blood cell count between patients younger than two years of age to the other groups was statistically significant. Forty four (15.3%) patients underwent surgical intervention. A direct correlation was found between leukocytosis and older age to surgery. CONCLUSIONS: Periorbital cellulitis occurs mainly in children and males and is less frequent in the summer. Children tend to have worse orbital involvement with lower temperatures than adults. Older age and leukocytosis are associated with surgical intervention.

An Arginine Deprivation Response Pathway Is Induced in Leishmania during Macrophage Invasion.

Amino acid sensing is an intracellular function that supports nutrient homeostasis, largely through controlled release of amino acids from lysosomal pools. The intracellular pathogen Leishmania resides and proliferates within human macrophage phagolysosomes. Here we describe a new pathway in Leishmania that specifically senses the extracellular levels of arginine, an amino acid that is essential for the parasite. During infection, the macrophage arginine pool is depleted due to its use to produce metabolites (NO and polyamines) that constitute part of the host defense response and its suppression, respectively. We found that parasites respond to this shortage of arginine by up-regulating expression and activity of the Leishmania arginine transporter (LdAAP3), as well as several other transporters. Our analysis indicates the parasite monitors arginine levels in the environment rather than the intracellular pools. Phosphoproteomics and genetic analysis indicates that the arginine-deprivation response is mediated through a mitogen-activated protein kinase-2-dependent signaling cascade.

Severe Acute Mastoiditis Admission is Not Related to Delayed Antibiotic Treatment for Antecedent Acute Otitis Media.

BACKGROUND: Delayed antibiotic treatment for acute otitis media (AOM) is recommended for children >6 months with nonsevere illness, no risk factors for complications or history of recurrent AOM. This study evaluates relationship between delayed antibiotic treatment for antecedent AOM and severity of subsequent acute mastoiditis admission. METHODS: A prospective observational study of children aged 0-14 years admitted with acute mastoiditis to 8 hospitals between 2007 and 2012 calculates rates of severe acute mastoiditis admission [defined by ≥1 of the following: complication (mastoid subperiosteal abscess, brain abscess and sagittal vein thrombosis), need for surgical procedure and duration of admission >6 days].Severe acute mastoiditis admissions in children with antecedent AOM treated with immediate antibiotics were compared with those with delayed antibiotic treatment. RESULTS: Antecedent AOM was diagnosed in 216 of 512 acute mastoiditis admissions (42.1%), of whom 159 (73%) immediately received antibiotics, and 57 (27%) had delayed antibiotic treatment. Higher rate of recurrent AOM was noted in the immediate compared with delayed antibiotic treatment group (29% vs. 8.7%, P = 0.0021). Complication rates were 19.5% versus 10.5% (P = 0.12), rates of surgical procedures required, 30% versus 10% (P = 0.0033); admission rates >6 days, 37% versus 29% (P = 0.28) for immediate antibiotic therapy and delayed antibiotic treatment. On logistic regression analysis, immediately treated AOM patients had increased need for surgery for acute mastoiditis with adjustment for history of recurrent AOM (relative risk: 3.2, 95% confidence interval: 1.4-7.0). CONCLUSIONS: Delayed antibiotic treatment for antecedent AOM is not associated with an increase in severity parameters in subsequent acute mastoiditis admission.

Incidence and risk factors for intussusception among children in northern Israel from 1992 to 2009: a retrospective study.

BACKGROUND: Determining the background incidence of intussusception is important in countries implementing rotavirus immunization. Rotavirus immunization was introduced into the routine infant immunization program in Israel during late 2010. Incidence and risk factors for intussusception were examined in children aged less than five years between 1992 and 2009. METHODS: Data were collected from medical records of children hospitalized due to intussusception (N = 190), and from control children (N = 295), at Carmel and Hillel Yaffe hospitals in northern Israel. RESULTS: The average annual incidence of intussusception in Jewish and Arab children aged less than five years was estimated at 36.1 (95% CI 17.0-76.5) vs. 23.2 per 100,000 (95% CI 9.3-57.9); for infants less than 12 months of age- 128.1 (95% CI 53.0-309.6) vs. 80.1 (95% CI 29.1-242.6) per 100,000. The risk of intussusception was higher in infants aged 3-5 months: OR 5.30 (95% CI 2.11-13.31) and 6-11 months: OR 2.53 (95% CI 1.13-5.62) when compared to infants aged less than 3 months; in those living in low vs high socioeconomic communities: OR 2.81 (95% CI 1.45-5.43), and in children with recent gastroenteritis: OR 19.90 (95% CI 2.35-168.32) vs children without recent gastroenteritis. Surgical reduction was required in 23.2%. The likelihood of surgery was significantly increased in patients presenting with bloody stool, in Arabs and those who were admitted to Hillel Yaffe Hospital. CONCLUSIONS: The incidence of intussusception prior to universal rotavirus immunization was documented in northern Israel. Despite the lower incidence, Arab patients underwent surgery more often, suggesting delayed hospital admission of Arab as opposed to Jewish patients.

Cat scratch disease during pregnancy.

OBJECTIVE: To describe the pregnancy outcome, including long-term follow-up of the offspring, of pregnant women with cat scratch disease. METHODS: A surveillance study performed over 19 years identified eight pregnant women with cat scratch disease. A case of cat scratch disease was defined as a patient with a history of cat contact with regional lymphadenitis, other manifestations, or a combination of these consistent with the disease and one or more confirmatory laboratory tests. The clinical and laboratory manifestations and pregnancy outcome of all women diagnosed with cat scratch disease during pregnancy are described. RESULTS: Five of the eight pregnant women had typical disease with regional lymphadenitis; two had regional lymphadenitis with arthralgia, myalgia, and erythema nodosum; and one had neuroretinitis. Delayed diagnosis was common, although all women had a history of recent cat exposure. One woman who presented with clinical cat scratch disease during the first month of pregnancy had a spontaneous abortion. Another elected to terminate the pregnancy because of concerns related to radiation associated with abdominal computed tomography scan performed as part of an evaluation for suspected malignancy. The other six women gave birth to healthy newborns without congenital anomalies. No sequelae were recorded in mothers or children during a median follow-up of 4.5 years (range 0.5-9.5 years). CONCLUSION: With the exception of one early spontaneous abortion in which causality to cat scratch disease could not be established, neither deleterious effects of cat scratch disease on newborns nor reports of long-term sequelae were found. Physicians, especially family physicians and obstetrician-gynecologists need to be more familiar with the clinical manifestations of cat scratch disease. Close monitoring of infected women during pregnancy is advisable until more data are available to determine the optimal diagnostic and therapeutic approach.

Incidence and clinical manifestations of adenoviral infection among children undergoing allogeneic stem cell transplantation.

BACKGROUND: Adenoviral infection in children undergoing stem cell transplantation is associated with significant morbidity and mortality. Identification of adenoviral infection by polymerase chain reaction from blood facilitates accurate and rapid diagnosis and surveillance. The incidence of adenoviral infection among children undergoing SCT in Israel is not known. OBJECTIVE: To estimate the incidence of adenoviral infection in pediatric SCT patients and to characterize the morbidity associated with proven infection. METHODS: Blood samples obtained weekly from children who underwent allogeneic SCT were retrospectively tested for adenovirus using standard PCR. A total of 657 samples collected from 32 patients were examined. Correlation was made between the presence of adenovirus in samples and clinical records. RESULTS: Of the 32 patients 4 had adenoviral infection by PCR (12.5%). Clinical disease was present in all four patients concurrent with positive PCR. Gastrointestinal complaints and abnormal hepatocellular enzymes were uniformly present. One patient died due to disseminated disease. T cell depletion was a significant risk factor for adenoviral infection (P = 0.03). CONCLUSIONS: In the patient population studied, the incidence of adenoviral infection in children undergoing SCT was 12.5%. The combination of gastrointestinal symptoms and abnormal hepatocellular enzymes should raise the suspicion of adenoviral infection, especially when occurring during the first few months after SCT.

Hemophagocytic lymphohistiocytosis associated with Epstein Barr virus and Leishmania donovani coinfection in a child from Cyprus.

We present a case of a 9-month-old girl from Cyprus with hemophagocytic lymphohistiocytosis associated with Epstein Barr virus and Leishmania donovani coinfection. Treatment with liposomal amphotericin B resulted in a dramatic resolution of clinical and laboratory abnormalities. To our knowledge, this is the first reported case of a coinfection-associated hemophagocytic lymphohistiocytosis and the first clinical report of visceral leishmaniasis infection in Europe by L. donovani.

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.