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Biomedical subjects

J E Koehler

Publications and source records attributed to J E Koehler.

At least 19 recordsLinked to original sources

Probable locally acquired mosquito-transmitted malaria in Georgia, 1999.

In July 1999, the Centers for Disease Control and Prevention received notification of a case of malaria in a 32-year-old female native of Colquitt County, Georgia, who had no history of travel into an area where malaria transmission is endemic. An epidemiological investigation confirmed the absence of risk factors, such as blood transfusion, organ transplantation, malariotherapy, needle sharing, or past malaria infection. Active case finding revealed no other infected persons in Colquitt County. Light trapping and larvae-dipping failed to identify adult or larval anophelines; however, Colquitt County is known to be inhabited by Anopheles quadrimaculatus, a competent malaria vector. The patient's home was located near housing used by seasonal migrant workers from regions of southern Mexico and Central America where malaria is endemic, one of whom may have been the infection source. The occurrence of malaria in this patient with no risk factors, except for proximity to potentially gametocytemic hosts, suggests that this illness probably was acquired through the bite of an Anopheles species mosquito.

Adult↗

Identification, characterization, and functional analysis of a gene encoding the ferric uptake regulation protein in Bartonella species.

Environmental iron concentrations coordinately regulate transcription of genes involved in iron acquisition and virulence via the ferric uptake regulation (fur) system. We identified and sequenced the fur gene and flanking regions of three Bartonella species. The most notable difference between Bartonella Fur and other Fur proteins was a substantially higher predicted isoelectric point. No promoter activity or Fur autoregulation was detected using a gfp reporter gene fused to the 204 nucleotides immediately upstream of the Bartonella fur gene. Bartonella henselae fur gene expression complemented a Vibrio cholerae fur mutant.

Amino Acid Sequence↗

Ocular bartonellosis.

PURPOSE: To review recent advances in the basic and clinical biology of Bartonella-related eye disease. METHOD: A review of the pertinent medical literature was performed. RESULTS: A number of novel Bartonella species have been identified over the past decade. Of these, Bartonella henselae, the etiologic agent in cat scratch disease, is most often associated with ocular complications, which may include Parinaud oculoglandular syndrome, neuroretinitis, and focal retinochoroiditis. Although cat and flea exposure appear to be the main risk factors for contracting cat scratch disease, the diagnosis of ocular bartonellosis relies primarily on the recognition of suggestive clinical signs in conjunction with positive serologic testing. B. henselae-associated ocular complications are usually self-limited but may be treated with doxycycline or erythromycin, with or without rifampin, when the infections are severe or sight-threatening. CONCLUSIONS: B. henselae infection is common and should be considered in patients with Parinaud oculoglandular syndrome, neuroretinitis, or focal retinochoroiditis, particularly when there is a history of cat or flea exposure.

Animals↗

Factors influencing a communitywide campaign to administer hepatitis A vaccine to men who have sex with men.

OBJECTIVES: A hepatitis A outbreak among men who have sex with men (MSM) led to a publicly funded vaccination campaign. We evaluated the MSM community's response. METHODS: A cohort of MSM from 5 community sites was surveyed. RESULTS: Thirty-four (19%) of 178 potential vaccine candidates received the vaccine during the campaign. We found a linear relation between the number of exposures to campaign information and the likelihood of vaccination (P < .001). Vaccination was independently associated with awareness of the outbreak and the vaccine, having had sexual relations with men for 12 years or longer, having recently consulted a physician, and routinely reading a local gay newspaper. CONCLUSIONS: The difficult task of vaccinating MSM can be aided by repetitive promotional messages, especially via the gay media.

Adult↗

Absence of Kaposi's sarcoma-associated herpesvirus DNA in bacillary angiomatosis-peliosis lesions.

Bartonella henselae and B. quintana induce an unusual vascular proliferative tissue response known as bacillary angiomatosis (BA) and bacillary peliosis (BP) in some human hosts. The mechanisms of Bartonella-associated vascular proliferation remain unclear. Although host factors probably play a role, microbial coinfection has not been ruled out. Because of the vascular proliferative characteristics noted in both Kaposi's sarcoma (KS) and BA and occasional colocalization of KS and BA, the possibility was explored that KS-associated herpesvirus (KSHV) might be associated with BA lesions. Tissues with BA and positive and negative control tissues were tested for the presence of KSHV DNA by a sensitive polymerase chain reaction assay. Only 1 of 10 BA tissues, a splenic biopsy, was positive in this assay; this tissue was from a patient with concomitant KS of the skin. Thus, KSHV is probably not involved in the vascular proliferative response seen in BA-BP.

Adult↗

Escherichia coli O157:H7 outbreak associated with an improperly chlorinated swimming pool.

A cluster of gastrointestinal illnesses, including one case of hemolytic-uremic syndrome and one culture-confirmed Escherichia coli O157:H7 infection, followed a trailer park pool party. We interviewed a cohort of party attendees and park residents. A primary case was defined as the first gastrointestinal illness within a household between 5 July and 20 July in which the titer of IgG antibody to E. coli O157 (if determined) was elevated. Of 51 party attendees and trailer park residents, 18 developed a gastrointestinal illness, including 10 who met the definition of a primary case. Swimming in the pool significantly increased the risk of primary illness (relative risk = 6.3; 95% confidence interval = 1.8-18.9). No other exposure was significantly associated with primary illness, after pool exposure was controlled for. The implicated pool had little to no chlorine added during the period of 4-10 July. This outbreak provides new evidence of the importance of proper pool maintenance in controlling the spread of E. coli O157:H7.

Chlorides↗

Identification of Bartonella species directly in clinical specimens by PCR-restriction fragment length polymorphism analysis of a 16S rRNA gene fragment.

It is now established that two species of Bartonella, namely, Bartonella henselae and B. quintana, cause bacillary angiomatosis in human immunodeficiency virus-infected patients. In addition, B. henselae causes cat scratch disease and B. quintana, B. henselae, and B. elizabethae can cause bacteremia and endocarditis in immunocompetent persons. We have developed a PCR-restriction fragment length polymorphism-based assay for direct detection and identification to species level of Bartonella in clinical specimens. This is accomplished by PCR amplification of Bartonella DNA using primers derived from conserved regions of the gene carrying the 16S ribosomal DNA, followed by restriction analysis using DdeI and MseI restriction endonucleases. We amplified a Bartonella genus-specific 296-bp fragment from 25 clinical samples obtained from 25 different individuals. Restriction analysis of amplicons showed that identical patterns were seen from digestion of B. henselae and B. quintana amplicons with DdeI, whereas a different unique pattern was seen by using the same enzyme with B. vinsonii and B. elizabethae. With MseI digestion, B. henselae and B. vinsonii gave nearly identical patterns while B. quintana and B. elizabethae gave a different pattern. By combining the restriction analysis data generated with MseI and DdeI, unique "signature" restriction patterns characteristic for each species were obtained. These patterns were useful in identifying the Bartonella species associated with each tissue specimen.

Angiomatosis, Bacillary↗

Use of retinal biopsy to diagnose Bartonella (formerly Rochalimaea) henselae retinitis in an HIV-infected patient.

A patient with the acquired immunodeficiency syndrome developed bilateral retinitis due to a Bartonella (formerly Rochalimaea) henselae infection. A retinal biopsy was performed when severe and progressive retinal infection failed to respond to empirical treatment for cytomegalovirus and Toxoplasma gondii. The biopsy specimen was stained with routine histopathological stains and the Steiner silver stain. Ribosomal DNA was extracted from formalinfixed, paraffin-embedded retinal tissue and amplified with the polymerase chain reaction assay, using Bartonella-specific primers. The amplified DNA fragment was cloned and sequenced. Staining with hematoxylin-eosin revealed tufts of proliferating vascular endothelium with numerous fusiformappearing cells, consistent with a diagnosis of bacillary angiomatosis. A Steiner silver stain revealed numerous small bacilli in the biopsy specimen. Amplification of DNA extracted from the tissue produced a fragment of 16S ribosomal DNA of the expected size; sequencing of the DNA fragment revealed that the infection was caused by B henselae. The retinal infection was treated with minocycline, doxycycline, and ciprofloxacin with improvement in visual acuity in the ensuing 12 weeks. To our knowledge, this is the first human immunodeficiency virus-infected patient with retinitis due to B henselae who was diagnosed by the identification of silver-staining bacilli and amplification and sequencing of B henselae with a polymerase chain reaction assay using a biopsy specimen of retinal tissue. Retinal biopsy is indicated, despite its potential for serious complications, in patients with acquired immunodeficiency syndrome who have a progressive, sight-threatening retinitis that is undiagnosed and unresponsive to therapy.

AIDS-Related Opportunistic Infections↗

Bartonella-associated infections.

Bartonella-associated infections occur in immunocompetent and immunocompromised patients. The spectrum of diseases caused by Bartonella species has expanded and now includes cat-scratch disease, bacillary angiomatosis, bacillary peliosis, bacteremia, endocarditis, and trench fever. Most Bartonella-associated infections that occur in North America and Europe are caused by B. henselae or B. quintana. The domestic cat serves as the major reservoir for B. henselae; the reservoir for the modern day B. quintana infection remains unknown. Methods used to diagnose Bartonella-associated infections include histopathologic analysis of biopsy specimens, culture of tissue samples, blood culture, and serology. Available data on treatment of Bartonella-associated infections remain relatively sparse but would suggest that erythromycin or doxycycline provide the best responses.

AIDS-Related Opportunistic Infections↗

Detection of Bartonella henselae by polymerase chain reaction in brain tissue of an immunocompromised patient with multiple enhancing lesions. Case report and review of the literature.

The authors report the first DNA-based diagnosis of Bartonella henselae cultured from a brain lesion in a patient with acquired immune deficiency syndrome. This human immunodeficiency virus-infected patient presented with altered mental status, fever, and diabetes insipidus. Magnetic resonance imaging revealed multifocal parenchymal and leptomeningeal involvement, which was confirmed on studies of tissue biopsy samples. Using the polymerase chain reaction and gene sequencing techniques, the authors definitively demonstrated the presence of B. henselae in the brain tissue biopsy specimen.

AIDS-Related Opportunistic Infections↗

Molecular epidemiology of bartonella infections in patients with bacillary angiomatosis-peliosis.

BACKGROUND: Bacillary angiomatosis and bacillary peliosis are vascular proliferative manifestations of infection with species of the genus bartonella that occur predominantly in patients infected with the human immunodeficiency virus. Two species, B. henselae and B. quintana, have been associated with bacillary angiomatosis, but culture and speciation are difficult, and there has been little systematic evaluation of the species-specific disease characteristics. We studied 49 patients seen over eight years who were infected with bartonella species identified by molecular techniques and who had clinical lesions consistent with bacillary angiomatosis-peliosis. METHODS: In this case-control study, a standardized questionnaire about exposures was administered to patients with bacillary angiomatosis-peliosis and to 96 matched controls. The infecting bartonella species were determined by molecular techniques. RESULTS: Of the 49 patients with bacillary angiomatosis-peliosis, 26 (53 percent) were infected with B. henselae and 23 (47 percent) with B. quintana. Subcutaneous and lytic bone lesions were strongly associated with B. quintana, whereas peliosis hepatis was associated exclusively with B. henselae. Patients with B. henselae infection were identified throughout the study period and were epidemiologically linked to cat and flea exposure (P< or =0.004), whereas those with B. quintana were clustered and were characterized by low income (P=0.003), homelessness (P = 0.004), and exposure to lice (P= 0.03). Prior treatment with macrolide antibiotics appeared to be protective against infection with either species. CONCLUSIONS: B. henselae and B. quintana, the organisms that cause bacillary angiomatosis-peliosis, are associated with different epidemiologic risk factors and with predilections for involvement of different organs.

Angiomatosis, Bacillary↗

Experimental and natural infection with Bartonella henselae in domestic cats.

Domestic cats were experimentally infected with culture propagated Bartonella henselae by intradermal (i.d.) and intravenous (i.v.) routes. Cats were more efficiently infected by the i.d. (8/8 cats) than by the i.v. (2/16) route. Bacteremia was detected 1-3 weeks following inoculation and lasted for most cats for 1-8 months. However, one naturally infected cat was observed for 24 months and was found to be cyclically bacteremic, with bacterial levels varying one hundred fold or more from one period to another. No clinical or hematologic abnormalities were observed in any of the infected cats, even at the peak of bacteremia. Two cats that had become abacteremic were resistant to reinfection when inoculated with B. henselae a second time. Horizontal transmission through intimate contact between bacteremic and susceptible cats did not occur, and antibody positive bacteremic queens did not transmit the infection to their kittens in utero, peri-partum or post-partum. Only four of the 18 kittens acquired detectable levels of maternal antibody following nursing, which disappeared by 6 weeks of age. These studies indicate that B. henselae exists in an almost perfect host-parasite relationship with its feline host, but that most cats can ultimately rid themselves of the infection. The susceptibility of cats to intradermal infection and the lack of direct cat-cat transmission are compatible with possible arthropod vectors.

Animals↗

Bacillary angiomatosis associated with myositis in a patient infected with human immunodeficiency virus.

A man with AIDS presented with a deep soft-tissue mass involving the right thigh. Biopsy of a skin lesion on the back and culture of a specimen from this lesion showed bacillary angiomatosis due to Bartonella (formerly Rochalimaea) quintana. Magnetic resonance imaging revealed a large heterogeneous mass involving the vastus medialis and intermedius muscles. Therapy with erythromycin caused rapid resolution of both the cutaneous lesion and the muscle lesion. Bartonella infection is proposed as an additional cause of bacterial myositis and expands the spectrum of presentation of bacillary angiomatosis.

AIDS-Related Opportunistic Infections↗

Bacillary angiomatosis of the cervix and vulva in a patient with AIDS.

BACKGROUND: Bacillary angiomatosis is a clinicopathologic entity that most often is identified in the skin of patients with AIDS. This report presents an example of bacillary angiomatosis of the female genital tract. CASE: Bacillary angiomatosis presented as red-purple nodules of the vulva and cervix in a 32-year-old woman with AIDS. Histologic examination revealed the lobular epithelioid vascular proliferation and hazy clumps of bacteria that characterize bacillary angiomatosis. The diagnosis was confirmed on Warthin-Starry-stained issue and by blood cultures, which were positive for Bartonella (Rochalimaea) henselae. CONCLUSION: Accurate diagnosis of this infection is important because 1) bacillary angiomatosis is commonly mistaken for Kaposi sarcoma, 2) it is effectively treated with inexpensive antibiotics, and 3) undiagnosed and/or untreated bacillary angiomatosis may lead to overwhelming disseminated infection and death.

AIDS-Related Opportunistic Infections↗

Bacillary angiomatosis and bacillary peliosis in patients infected with human immunodeficiency virus: clinical characteristics in a case-control study.

Clinical characteristics associated with bacillary angiomatosis and bacillary peliosis (BAP) in patients with human immunodeficiency virus (HIV) infection were evaluated in a case-control study; 42 case-patients and 84 controls were matched by clinical care institution. Case-patients presented with fever (temperature, > 37.8 degrees C; 93%), a median CD4 lymphocyte count of 21/mm3, cutaneous or subcutaneous vascular lesions (55%), lymphadenopathy (21%), and/or abdominal symptoms (24%). Many case-patients experienced long delays between medical evaluation and diagnosis of BAP (median, 4 weeks; range, 1 day to 24 months). Case-patients were more likely than controls to have fever, lymphadenopathy, hepatomegaly, splenomegaly, a low CD4 lymphocyte count, anemia, or an elevated serum level of alkaline phosphatase (AP) (P < .001). In multivariate analysis, a CD4 lymphocyte count of < 200/mm3 (matched odds ratio [OR], 9.9; P < .09), anemia reflected by a hematocrit value of < 0.36 (OR, 19.7; P < .04), and an elevated AP level of > or = 2.6 mukat/L (OR, 23.9; P < .05) remained associated with disease after therapy with zidovudine was controlled for. BAP should be considered an AIDS-defining opportunistic infection and should be included in the differential diagnosis for febrile, HIV-infected patients with cutaneous or osteolytic lesions, lymphadenopathy, abdominal symptoms, anemia, or an elevated serum level of AP.

AIDS-Related Opportunistic Infections↗

Granulomatous hepatitis and necrotizing splenitis due to Bartonella henselae in a patient with cancer: case report and review of hepatosplenic manifestations of bartonella infection.

Bacillary angiomatosis and the related disorders of bacillary peliosis hepatis and bacillary splenitis are manifestations of infection with Bartonella henselae and Bartonella quintana in immunocompromised persons. B. henselae infection, but not B. quintana infection, is linked to contact with cats and is presumed to cause visceral cat-scratch disease. We reports a case of visceral infection by B. henselae in an adult patient with cancer who was receiving chemotherapy and had had no contact with a cat or dog. The patient--whose illness was eventually diagnosed on the basis of findings of histologic, polymerase chain reaction, and serological studies--was treated with doxycycline and rifampin, and the infection resolved. In addition, 41 cases of documented or suspected bartonella infection of the liver, spleen, or both in immunocompetent or immunocompromised hosts are reviewed.

Antineoplastic Agents↗