Advanced HIV Infection Research Articles

7.0 Obstetric management

7.0 Obstetric management

Quality of Life Outcomes of Antiretroviral Treatment for HIV/AIDS Patients in Vietnam

ObjectiveThis study assessed health-related quality of life (HRQOL) and its related factors in HIV/AIDS patients taking antiretroviral treatment (ART) in Vietnam.MethodsA cross-sectional study was conducted with 1016 patients (36.2% women, mean age = 35.4) in three epicenters of Vietnam, including Hanoi, Hai Phong, and Ho Chi Minh City. HRQOL was assessed using the Vietnamese version of the WHOQOL-HIV BREF. Factor analysis classified measure items into six HRQOL dimensions, namely Physical, Morbidity, Social, Spirituality, Performance, and Environment. Tobit censored regression models were applied to determine associations of patient’s characteristics and HRQOL domain scores.ResultsInternal consistency reliability of the six domains ranged from 0.69 to 0.89. The WHOQOL-HIV BREF had a good discriminative validity with patient’s disease stages, CD4 cell counts, and duration of ART. In a band score of (4, 20), six domains were moderate; “Environment” had the highest score (13.8±2.8), and “Social” had the lowest score (11.2±3.3). Worse HRQOL were observed in patients at provincial and district clinics. Those patients who were male, had higher educational attainment, and are employed, reported better HRQOL. In reduced regression models, poorer HRQOL was found in patients who had advanced HIV infection and had CD4 cell count <200 cells/mL. Patients reported significantly poorer Physical and Social in the 1st year ART, but moderately better Performance, Morbidity, Spirituality, and Environment from the 2nd year ART, compared to those not-yet-on ART.ConclusionStrengthening the quality of ART services at the provincial and district levels, gender-specific impact mitigation, and early treatment supports are recommended for further expansion of ART services in Vietnam. Regular assessments of HRQOL may provide important indicators for monitoring and evaluating HIV/AIDS services.

Monocyte Activation Markers in Cerebrospinal Fluid Associated With Impaired Neurocognitive Testing in Advanced HIV Infection

Activated monocytes/macrophages play a role in severe forms of HIV-associated neurocognitive disorders (HAND), but little is known about the mechanisms driving milder forms that are prevalent despite combination antiretroviral therapy (cART). To examine relationships of monocyte activation markers to HAND of varying severity, we compared plasma and cerebrospinal fluid (CSF) biomarker levels with neurocognitive test scores in HIV+ subjects. Plasma and CSF soluble CD14 (sCD14), CCL2, and interleukin (IL) 6 were measured by enzyme-linked immunosorbent assay in 67 HIV+ subjects with nadir CD4 <300, and CSF inflammatory biomarkers were measured by multiplex assay in 14 subjects on suppressive cART. Eighty-two percent were on cART, with 31% having undetectable plasma viral load (VL). CSF sCD14 was increased in subjects with impaired neurocognitive testing (P = 0.02), correlated inversely with global T scores in subjects with detectable but not undetectable plasma VL (P = 0.02), and yielded higher area under the receiver operating characteristic curve values for predicting impaired T scores (0.659) than plasma or CSF VL and current or nadir CD4 counts in single-marker and multivariate models. CSF sCD14, IL-6, IL-8, CCL2, CCL3, CXCL10, and interferon (IFN) gamma were increased in subjects on suppressive cART regardless of cognitive status and predicted patient class in unsupervised analyses, with IL-8, CCL2, and IFNγ explaining most of the variance. CSF sCD14 is associated with impaired neurocognitive testing in patients with HIV on nonsuppressive cART, suggesting potential utility as a biomarker to monitor HAND progression. CSF sCD14, IL-6, IL-8, CCL2, CCL3, CXCL10, and IFNγ remain elevated in patients on suppressive cART regardless of cognitive status, implying ongoing intrathecal inflammation even in the absence of clinical manifestations.

47 YEAR-OLD MAN WITH HIV INFECTION AND HEMIPLEGIA

CNS aspergillosis is often missed in the setting of advanced HIV infection, especially in the absence of presumed risk factors such as neutropenia or prior steroid treatment. We describe the postmortem evaluation of the brain of a patient with AIDS that developed progressive neurologic deterioration. Sequence brain MRIs, CSF analysis, and multiple presumed treatments failed to reveal the possible causes or improve his ongoing condition. His brain autopsy showed numerous abscesses with septated hyphae consistent with CNS angioinvasive aspergillosis.

Levels of procalcitonin, C-reactive protein and neopterin in patients with advanced HIV-1 infection

Objectives. To compare the value of procalcitonin, C-reactive protein (CRP) and neopterin as indicators of immune deficiency, co-infection, efficacy of treatment, and disease progression, in patients with advanced HIV-1 infection.&#x0D; &#x0D; Design. Cross-sectional, investigating baseline blood measurements and clinical observations in 82 HIV-positive patients divided into an antiretroviral treatment (ART) group and an ART-naïve group.&#x0D; &#x0D; Setting. Secondary general hospital in Pretoria.&#x0D; &#x0D; Results. Procalcitonin and CRP levels showed no significant differences between the ART and ART-naïve groups, and no correlations with CD4 counts or viral loads. CRP levels were significantly higher with TB co-infection (p

Association of Mal/TIRAP S180L variant polymorphism with decreased infection risk in patients with advanced HIV-1 infection

ObjectivesMyD88 adaptor-like (Mal/TIRAP) is an adaptor protein bridging activation of Toll-like receptors 2 and 4 after stimulation by exogenous and endogenous ligands. We investigated the association between the presence of the S180L SNP of Mal and the risk of severe infection in individuals with human immunodeficiency virus (HIV)-1 infection. MethodsThe SNP S180L was determined in a cohort of 179 HIV-1 infected Greek patients. Analysis of the prevalence of this SNP in relation to the infectious complications was evaluated. ResultsOne hundred and thirty-two (73.3%) patients were bearing the wild type haplotype, 43 (24%) were heterozygous for the SNP, and four (2.2%) were homozygous for the variant allele. The individuals with a nadir CD4 count <200cells/mm3 who carried the 180L variant demonstrated a 4-fold decrease in the odds ratio (OR) for any serious infection compared with those who carried the wild-type 180S genotype (OR 0.58 vs OR 2.6, p=0.016). ConclusionsThis study suggest a protection effect of the Mal S180L SNP against serious infections in HIV-1 infected individuals with low CD4 cell counts.

FEVER IN HIV-INFECTED PATIENTS: LESS FREQUENT BUT STILL COMPLEX

Fever was a common symptom in patients with Human Immunodeficiency Virus (HIV) infection in the early phases of the epidemic. Fever of Unknown Origin (FUO) was frequent in HIV-patients and conditions causing FUO were often opportunistic conditions. The HIV-epidemic continues to expand, but access to effective antiretroviral therapy is also expanding, resulting in a growing number of HIV-infected patients less likely to be severely immunocompromised and less likely to present opportunistic conditions. Yet part of newly diagnosed patients continue to present with advanced HIV-infection and are still at high risk of opportunistic conditions. This epidemiological evolution strongly influences the spectrum of conditions causing fever and FUO in HIV-patients. While some patients with HIV-associated fever and FUO may still be suffering from opportunistic conditions classically associated with HIV-related FUO, many others will have causes of fever that are similar to the non-HIV-infected population or to classical FUO. Strategies for diagnosis and treatment of fever and its causes in HIV-infected patients need to take into account this evolution.

HLA-G expressing Tregs inhibit bystander immune activation in HIV-1 infection (170.27)

Abstract T cells expressing the HLA class Ib molecule, HLA-G, represent an emerging non-classical population of regulatory T cells (Tregs). However, the functional role of these cells during HIV-1 infection remains unclear. Here, we performed a comprehensive investigation of HLA-G- expressing Tregs in patients with different rates of HIV-1 disease progression. Using flow cytometry, we found the proportion of HLA-G-expressing CD4 and CD8 T cells were significantly reduced in individuals with progressive HIV-1 infection (p&amp;lt;0.001 for both CD4 and CD8 T cells). Moreover, HLA-G expressing Tregs were inversely correlated with phenotypic markers of immune activation, CD38 and HLA-DR (p=0.026 for CD4 and p&amp;lt;0.005 for CD8 T cells), and positively correlated with CD4 T cell counts. Functional co-culture assays indicated that HLA-G-expressing CD4 and CD8 T cells were able to potently inhibit TCR-independent bystander activation, but only weakly inhibited TCR-dependent cytokine-secretion and proliferative properties of HIV-1-specific T cells. Furthermore, in vitro infection assay suggested HLA-G expressing Treg were more susceptible to HIV-1 infection (p=0.0039). These data indicate an important role of HLA-G+ Tregs for balancing bystander immune activation and anti-viral immune activity in HIV-1 infection, and suggest that the loss of these cells during advanced HIV-1 infection may contribute to immune dysregulation and HIV-1 disease progression.

The Cost-Effectiveness of Cotrimoxazole in People With Advanced HIV Infection Initiating Antiretroviral Therapy in Sub-Saharan Africa

In sub-Saharan Africa, high mortality rates have been reported among patients with advanced HIV infection initiating antiretroviral therapy (ART). We evaluated the cost-effectiveness of expanding access to cotrimoxazole (CTX) for persons with HIV in averting mortality during the first 6 months of ART. We also evaluated possible cost savings related to prevention of specific opportunistic infections (OIs). We developed a decision-analytic model to estimate the incremental cost, deaths averted, and incremental cost-effectiveness ratio. The model compared 2 scenarios for providing CTX and evaluated potential benefits of increased CTX coverage in reducing deaths and cases of OI. The base case scenario represents an estimated current level of CTX coverage among adults initiating ART in low-income countries (65%). The comparator is 97% coverage (excluding only those with contraindications to CTX). We conducted sensitivity analyses on all parameters in the model. Full coverage reduced deaths from 94 to 72 per 1000 patients, averting 22 deaths during the first 6 months of ART compared with the base case. The incremental cost of moving from base case to full coverage was estimated at $3.29 per person on ART and $146.91 per death averted over 6 months. Additional benefits from averted OI cases would likely be realized as well as savings from averted OI treatment costs. Our findings suggest that expanding CTX coverage is a cost-effective approach to reducing mortality among patients who present with advanced HIV and initiate ART. The expansion of coverage may also yield benefits for OIs.

Cost-Effectiveness of Tuberculosis Diagnostic Strategies to Reduce Early Mortality Among Persons With Advanced HIV Infection Initiating Antiretroviral Therapy

In sub-Saharan Africa, patients with advanced HIV experience high mortality during the first few months of antiretroviral therapy (ART), largely attributable to tuberculosis (TB). We evaluated the cost-effectiveness of TB diagnostic strategies to reduce this early mortality. We developed a decision analytic model to estimate the incremental cost, deaths averted, and cost-effectiveness of 3 TB diagnostic algorithms. The model base case represents current practice (symptoms screening, sputum smear, and chest radiography) in many resource-limited countries in sub-Saharan Africa. We compared the current practice with World Health Organization (WHO)-recommended practice with culture and WHO-recommended practice with the Xpert mycobacterium tuberculosis and resistance to rifampicin test and considered relevant medical costs from a health system perspective using the timeframe of the first 6 months of ART. We conducted univariate and probabilistic sensitivity analyses on all parameters in the model. When considering TB diagnosis and treatment and ART costs, the cost per patient was $850 for current practice, $809 for the algorithm with Xpert test, and $879 for the algorithm with culture. Our results showed that both WHO-recommended algorithms avert more deaths among TB cases than does the current practice. The algorithm with Xpert test was least costly at reducing early mortality compared with the current practice. Sensitivity analyses indicated that cost-effectiveness findings were stable. Our analysis showed that culture or Xpert were cost-effective at reducing early mortality during the first 6 months of ART compared with the current practice. Thus, our findings provide support for ongoing efforts to expand TB diagnostic capacity.

A novel assay detecting recall response to Mycobacterium tuberculosis: Comparison with existing assays

A strategy to reduce the burden of active TB is isoniazid preventive therapy for latent TB infection (LTBI). However, current assays used to diagnose LTBI all have limitations. In these proof of concept studies, we compared the agreement of a novel flow cytometry assay detecting CD25/CD134 co-expression with QuantiFERON-TB Gold In-Tube (QFN-GIT) and Tuberculin skin test (TST) in the detection of recall immune response to TB. The CD25/CD134 assay, QFN-GIT and TST were performed on 74 participants referred for TB screening in Sydney and on 50 participants with advanced HIV infection (CD4 ≤ 350 × 10(6) cells/L) in Bangkok. The agreement between CD25/CD134 assay and QFN-GIT was 93.2% (Kappa 0.631 95% CI 0.336-0.926) in Sydney and 90% (Kappa 0.747 95% CI 0.541-0.954) in Bangkok. Discordant results occurred around the cut off of both tests. The agreement between CD25/CD134 assay and TST was 73.6% (Kappa 0.206 95% CI 0.004-0.409) in Sydney and 84% (Kappa 0.551 95% CI 0.296-0.806) in Bangkok. The CD25/CD134 assay showed good agreement with QFN-GIT in detecting recall response to TB both in well and less resourced setting as well as in persons with advanced HIV infection. Further study into the performance of this assay is thus warranted.

Monocyte Activation Markers in Cerebrospinal Fluid Are Associated with Impaired Neurocognitive Testing in Advanced HIV Infection (P01.255)

Monocyte Activation Markers in Cerebrospinal Fluid Are Associated with Impaired Neurocognitive Testing in Advanced HIV Infection (P01.255)

Comparison the Radiologic Findings of Pulmonary Tuberculosis Among HIV-Seropositive With HIV-Seronegative Patients

: Background: Approximately 1.8 million of the world’s population is infected with both M.tuberculosis (TB) and HIV. HIV-seropositive patients with TB may have radiographically atypical presentations.Objectives: This study aimed to determine whether there was any difference in radiological presentation of pulmonary TB between HIV-seropositive and HIV-seronegative patients.Patients and Methods: Information on 204 patients who were admitted with a diagnosis of pulmonary TB to the infectious ward of Razi Hospital, Ahvaz, between 2004 and 2008 was obtained from their records. They were divided into HIV-seropositive and HIV-seronegative groups. All clinical signs and symptoms and radiological findings were extracted from each patient file and recorded in a questionnaire.Results: Normal thoracic radiography, pleural effusion, milliary pattern, and hilar and mediastinal lymphadenopathy were more common in the HIV-seropositive group. Pulmonary infiltration and cavitary lesions in Chest X-ray (CXR) were more frequent in the HIV-seronegative group. The prevalence of fibrosis in HIV-seronegative patients was higher than in HIV-seropositive subjects. Upper lobe pulmonary involvement in HIV-seropositive patients was less frequent than HIV-seronegative persons due to their immunodeficiency.Conclusions: Radiological presentation of pulmonary TB differs between HIV-seropositive and HIV-seronegative patients due to progressive immunodeficiency from HIV infection. Implication for health policy/practice/research/medical education:As pulmonary tuberculosis is an important opportunistic infection in patients with advanced HIV infection, delay in diagnosis and treatment may lead to severe morbidity and death. So clinicians should be aware about different and sometimes atypical radiographic manifestations of pulmonary tuberculosis in HIV infected patients. The importance of this study is to define such atypical. Please cite this paper as:Ahmadi F, Salmanzadeh S, Kimyai M, Comparison the Radiologic Findings of Pulmonary Tuberculosis Among HIV-Seropositive With HIV-Seronegative Patients. Jundishapur J Microbiol.2012;5(2):421-3. DOI: 10.5812/jjm.3536 Copyright © 2012 Kowsar Corp. All rights reserved.

Shelterin Dysfunction and p16 INK4a -Mediated Growth Inhibition in HIV-1-Specific CD8 T Cells

HIV-1-specific cytotoxic T cell responses are expanded during advanced HIV-1 infection but seem unable to effectively protect the host against disease progression. These cells are able to produce gamma interferon and remain metabolically active but have defective proliferative activities, shortened telomeric DNA, and other signs of accelerated aging. To investigate the molecular mechanisms underlying the premature senescence of HIV-1-specific T cells, we focused here on the expression and function of a group of six nucleoproteins that are responsible for protecting and maintaining the structural integrity of telomeric DNA and are commonly referred to as "shelterin." We show that in progressive HIV-1 infection, the two major shelterin components TRF2 and TPP1 are selectively reduced in HIV-1-specific CD8 T cells, but not in T cells recognizing alternative viral species. This coincided with increased recruitment of 53BP1, a prominent DNA damage response factor, to telomeric DNA sites and was associated with elevated expression of the tumor suppressor p16(INK4a), which causes cellular growth inhibition in response to structural DNA damage. Notably, defective shelterin function and upregulation of p16(INK4a) remained unaffected by experimental blockade of PD-1, indicating a possibly irreversible structural defect in HIV-1-specific CD8 T cells in progressors that cannot be overcome by manipulation of inhibitory cell-signaling pathways. These data suggest that shelterin dysfunction and ensuing upregulation of the tumor suppressor p16(INK4a) promote accelerated aging of HIV-1-specific T cells during progressive HIV-1 infection.

Lipoarabinomannan in urine during tuberculosis treatment: association with host and pathogen factors and mycobacteriuria

BackgroundDetection of lipoarabinomannan (LAM), a Mycobacterium tuberculosis (Mtb) cell wall antigen, is a potentially attractive diagnostic. However, the LAM-ELISA assay has demonstrated variable sensitivity in diagnosing TB in diverse clinical populations. We therefore explored pathogen and host factors potentially impacting LAM detection.MethodsLAM-ELISA assay testing, sputum smear and culture status, HIV status, CD4 cell count, proteinuria and TB outcomes were prospectively determined in adults diagnosed with TB and commencing TB treatment at a South African township TB clinic. Sputum TB isolates were characterised by IS61110-based restriction fragment length polymorphism (RFLP) and urines were tested for mycobacteriuria by Xpert® MTB/RIF assay.Results32/199 (16.1%) of patients tested LAM-ELISA positive. Median optical density and proportion testing LAM positive remained unchanged during 2 weeks of treatment and then declined over 24 weeks. LAM was associated with positive sputum smear and culture status, HIV infection and low CD4 cell counts but not proteinuria, RFLP strain or TB treatment outcome. The sensitivity of LAM for TB in HIV-infected patients with CD4 counts of ≥ 200, 100-199, 50-99, and < 50 cells/μl, was 15.2%, 32%, 42.9%, and 69.2% respectively. Mycobacteriuria was found in 15/32 (46.9%) of LAM positive patients and in none of the LAM negative controls.ConclusionsUrinary LAM was related to host immune factors, was unrelated to Mtb strain and declined steadily after an initial 2 weeks of TB treatment. The strong association of urine LAM with mycobacteriuria is a new finding, indicating frequent TB involvement of the renal tract in advanced HIV infection.

Doxycycline and HIV Infection Suppress Tuberculosis-induced Matrix Metalloproteinases

Tuberculosis kills more than 1.5 million people per year, and standard treatment has remained unchanged for more than 30 years. Tuberculosis (TB) drives matrix metalloproteinase (MMP) activity to cause immunopathology. In advanced HIV infection, tissue destruction is reduced, but underlying mechanisms are poorly defined and no current antituberculous therapy reduces host tissue damage. To investigate MMP activity in patients with TB with and without HIV coinfection and to determine the potential of doxycycline to inhibit MMPs and decrease pathology. Concentrations of MMPs and cytokines were analyzed by Luminex array in a prospectively recruited cohort of patients. Modulation of MMP secretion and Mycobacterium tuberculosis growth by doxycycline was studied in primary human cells and TB-infected guinea pigs. HIV coinfection decreased MMP concentrations in induced sputum of patients with TB. MMPs correlated with clinical markers of tissue damage, further implicating dysregulated protease activity in TB-driven pathology. In contrast, cytokine concentrations were no different. Doxycycline, a licensed MMP inhibitor, suppressed TB-dependent MMP-1 and -9 secretion from primary human macrophages and epithelial cells by inhibiting promoter activation. In the guinea pig model, doxycycline reduced lung TB colony forming units after 8 weeks in a dose-dependent manner compared with untreated animals, and in vitro doxycycline inhibited mycobacterial proliferation. HIV coinfection in patients with TB reduces concentrations of immunopathogenic MMPs. Doxycycline decreases MMP activity in a cellular model and suppresses mycobacterial growth in vitro and in guinea pigs. Adjunctive doxycycline therapy may reduce morbidity and mortality in TB.

Costs of HIV/AIDS: A case study in Iran

Advanced HIV (AIDS) is a phenomenon that its social, cultural and economic aspects are very broad and it can be regarded as an important obstacle in human progress. Considering the possibility of the future expansion, especially in developing countries with limited resources, thinking about its economic aspect is inevitable. The aim of this study was to calculate advanced and non-advanced HIV infection costs to patients in the selected referral centers in Iran. This is the kind of descriptive and cross-sectional study that was carried out on 120 out of 400 patients in the selected referral centers in Iran (the largest referral canters providing services to patients with advanced and non- advanced HIV) in four groups including advanced HIV with addiction, advanced HIV without addiction, non- advanced HIV with addiction and non advanced HIV without addiction in 2010. The study involves collecting data from available resources (including patient files and referral to the relevant centers) and interviews with patients and according to a valid questionnaire. The average annual total cost in groups first to forth were $18,583.44, $16,135.16, $7,029.48 and $7,007.44 respectively (P<0.01). Also the average of direct and indirect costs was significant (P<0.01). Considering the high costs of the disease and the low average age and education level in the study, using the evidence based educational intervention in order to increase the level of awareness to prevent further spread of the disease especially among the younger generation can lead to reduce the expenditure.

Suboptimal patterns of provider initiated HIV testing and counselling, antiretroviral therapy eligibility assessment and referral in primary health clinic attendees in Blantyre, Malawi*

ObjectiveTo understand reasons for suboptimal and delayed uptake of antiretroviral therapy (ART) by describing the patterns of HIV testing and counselling (HTC) and outcomes of ART eligibility assessments in primary clinic attendees.MethodsAll clinic attendances and episodes of HTC were recorded at two clinics in Blantyre. A cohort of newly diagnosed HIV-positive adults (>15 years) was recruited and exit interviews undertaken. Logistic regression models were constructed to investigate factors associated with referral to start ART. Qualitative interviews were conducted with providers and patients.ResultsThere were 2398 episodes of HTC during 18 021 clinic attendances (13.3%) between January and April 2011. The proportion of clinic attendees undergoing HTC was lowest in non-pregnant women (6.3%) and men (8.5%), compared with pregnant women (47.2%). Men had more advanced HIV infection than women (79.7% WHO stage 3 or 4 vs. 56.4%). Problems with WHO staging and access to CD4 counts affected ART eligibility assessments; only 48% completed ART eligibility assessment, and 54% of those reporting WHO stage 3/4 illnesses were not referred to start ART promptly. On multivariate analysis, HIV-positive pregnant women were significantly less likely to be referred directly for ART initiation (adjusted OR: 0.29, 95% CI: 0.13–0.63).ConclusionsThese data show that provider-initiated testing and counselling (PITC) has not yet been fully implemented at primary care clinics. Suboptimal ART eligibility assessments and referral (reflecting the difficulties of WHO staging in primary care) mean that simplified eligibility assessment tools are required to reduce unnecessary delay and attrition in the pre-ART period. Simplified initiation criteria for pregnant women, as being introduced in Malawi, should improve linkage to ART.

Thrombotic microangiopathic syndromes associated with drugs, HIV infection, hematopoietic stem cell transplantation and cancer

Thrombotic microangiopathy (TMA) has multiple etiologies. In the four disorders described in this review, the primary organ involved is the kidney. Drug-associated TMA can be an acute, immune-mediated disorder or the result of gradual, dose-dependent toxicity. TMA may occur in patients with advanced HIV infection, possibly mediated by angio-invasive infections. TMA following allogeneic hematopoietic stem cell transplantation may also be caused by drug toxicity; the pathogenesis may involve inhibition of vascular endothelial cell growth factor in renal podocytes. Malignancies of many types with systemic microvascular involvement may cause TMA. Recognition that these syndromes may mimic TTP is important to provide appropriate management and to avoid the inappropriate use of plasma exchange treatment.

Cat scratch disease in Australia

Companion animals such as cats are important for their health benefits. However, one of the risks of bringing cats into the household is cat scratch disease (CSD), with kittens or stray cats posing the highest risk. CSD is a clinical syndrome caused mainly by Bartonella henselae and is characterised by regional lymphadenopathy in patients with a history of close cat contact within three months of onset of symptoms. In most cases, CSD is a benign, self-limited infection, with more severe infections occurring only rarely in immunocompetent people. However, in immunocompromised patients, including those post-organ transplantation or with advanced HIV infection, the disease can be more severe and avoiding exposure needs to be considered. Improving flea control is also important, as transmission among cats occurs via the cat flea Ctenocephalides felis. To add to the data on B. henselae in Australia, I will report on some previously unpublished data on the seroprevalence and percentage of culture positives in WA domestic cats.