Legionella Pneumonia and AIDS

Although infections with the novel pandemic 2009 influenza A (H1N1) virus (A/H1N1/2009) appeared to be relatively mild during the first summer of circulation ('off season'), there has been significant morbidity and hospitalization and several fatal cases. Thus, rapid detection of A/H1N1/2009 is crucial for efficient treatment and infection control measures. In contrast to seasonal influenza, where point-of-care (POC) rapid antigen tests and direct fluorescent antibody (DFA) staining ensure rapid detection, diagnosis of A/H1N1/2009 has so far been based on RT-PCR. This study retrospectively compared the performance of the Quidel QuickVue POC test, DFA staining and virus isolation with that of RT-PCR for A/H1N1/2009 detection in 526 respiratory specimens collected during the first wave of the outbreak from May to September 2009. A/H1N1/2009 was detected in 9.1% (48/526) of samples. One hundred and thirty-seven of the A/H1N1/2009 PCR-negative samples were additionally tested using a RealAccurate Respiratory RT-PCR panel, revealing other respiratory viruses (mainly entero/rhino- and adenoviruses) in 42.3% (58/137). All methods analysed detected A/H1N1/2009 with excellent specificity but different sensitivities (POC test: 18.2%; DFA staining: 38.7%; virus isolation: 45.7%). Therefore, the POC test was not suitable for diagnosis, detecting A/H1N1/2009 only if present in high concentrations (corresponding median Ct value=19.0; range=16.5-21.4). DFA staining was also able to detect A/H1N1/2009 in specimens with a lower virus concentration (median Ct value=24.0; range=16.5-29.8). Virus isolation, which was positive after a median time of 7.5 days, was too time-consuming. In summary, DFA staining is superior to POC testing and may be appropriate for patients expected to have a rather high level of virus replication. Nevertheless, in DFA-negative specimens, A/H1N1/2009 should be excluded by RT-PCR.

Although an aggressive form of Kaposi's sarcoma often develops in patients with the acquired immunodeficiency syndrome, most patients die due to opportunistic infections rather than the direct effects of this tumor. Because Kaposi's sarcoma has caused pulmonary dysfunction in a number of our patients, we attempted to characterize features of pulmonary dysfunction induced by Kaposi's sarcoma. In 66 patients with Kaposi's sarcoma treated between 1982 and 1984 there were 30 episodes of pulmonary dysfunction that resulted in a biopsy. Six episodes were due to pulmonary Kaposi's sarcoma alone, and 6 additional episodes were due to Kaposi's sarcoma and associated opportunistic infections. Clinical and radiologic features of pulmonary Kaposi's sarcoma an infection were indistinguishable. Pulmonary Kaposi's sarcoma could only be documented in large tissue sections available from open-lung biopsy or autopsy samples. Because chemotherapy or radiation therapy appears to provide palliation, clinicians should recognize Kaposi's sarcoma as a cause of pulmonary disease in patients with the acquired immunodeficiency syndrome.

Digene's Hybrid Capture 2 (HC2) CT/GC, CT-ID, and GC-ID DNA tests were evaluated by comparison to traditional culture methods for detecting Chlamydia trachomatis and Neisseria gonorrhoeae infections in 669 cervical specimens from high-risk female populations attending two sexually transmitted disease clinics. For detection of either or both infections, the HC2 CT/GC test algorithm had 93.8% sensitivity and 95.9% specificity compared to those of culture. After resolution of discrepant results by direct fluorescent-antibody (DFA) staining or PCR assay, the relative sensitivity and specificity of the HC2 CT/GC test algorithm increased to 94.8 and 99.8%, while the values for culture were 83.6% (McNemar's P value, 0.0062) and 100%, respectively. For detection of the individual pathogens, the relative sensitivities for the HC2 CT-ID and GC-ID tests were 97.2 and 92.2% and the specificities were greater than 99% compared to culture adjucated by DFA staining and PCR. Test performance varied at the two clinics: the HC2 CT/GC algorithm, CT-ID, and GC-ID tests had significantly higher sensitivities (McNemar's P value, <0.05) than that of culture for the population at one clinic as well as for the combined populations. At the other clinic, the HC2 tests performed as well as culture.

Objective To explore the clinical application value of fluorescent immunoassay kit for influenza virus antigen detection by comparing the method to the direct fluorescent antibody staining and the reverse transcriptase polymerase chain reaction (RT-PCR) of influenza virus nucleic acids. Methods From July to December 2017, 350 patients in the fever clinic were examined by the fluorescent immunoassay kit for influenza virus antigen detection (Sofia FIA), direct fluorescent antibody staining (DFA) and RT-PCR of influenza virus nucleic acids. Results A total of 186 cases of influenza A/B viruses were detected by Sofia FIA, with an overall positive detection rate of 53.1%, and the detection rates of influenza A and B viruses were 35.4% and 17.7%, respectively. Compared to RT-PCR, the results of sensitivity, specificity, positive predictive value, negative predictive value, consistency rate and kappa value of Sofia FIA were 89.4%, 100.0%, 100.0%, 86.6%, 93.7% and 0.873 in the combined detection of influenza A/B viruses; 87.9%, 100.0%, 100.0%, 92.5%, 95.1% and 0.897 in the detection of influenza A virus; and were 92.5%, 100.0%, 100.0%, 98.3%, 98.6% and 0.952 in the detection of influenza B virus, respectively. Compared to RT-PCR, the results of sensitivity, specificity, positive predictive value, negative predictive value, consistency rate and kappa value of DFA were 83.2%, 100.0%,100.0%, 80.2%, 90.0% and 0.800 in the combined detection of influenza A/B viruses; 82.3%, 100.0%, 100.0%, 89.3%, 92.9% and 0.847 in the detection of influenza A virus; and were 85.1%, 100.0%, 100.0%, 96.6%, 97.1% and 0.902 in the detection of influenza B virus, respectively. Conclusions Sofia FIA and DFA had high sensitivity and specificity, and were in consistency with RT-PCR. The methods showed have certain clinical significance in the screening of influenza. Key words: Influenza; Rapid detection of influenza virus; Fluorescent immunoassay; Diagnosis

“Won’t Get Fooled Again” (by Tuberculosis)

Vesiculobullous Lyme disease: A case series

Aerosolized Pentamidine Prophylaxis

Successful treatment of AIDS-related pulmonary Kaposi's sarcoma with liposomal daunorubicin.

PULMONARY KAPOSI SARCOMA WITH ASSOCIATED RECURRENT CHYLOTHORAX

World AIDS Day: 40 years of an evolving pulmonary landscape.

OBJECTIVE:This retrospective descriptive study was undertaken to highlight the diagnostic features and natural history of pulmonary Kaposi's sarcoma (KS).METHODS:Thirty-three patients with symptomatic pulmonary KS were assembled from a cohort of 239 patient with KS. Pulmonary KS was diagnosed by visualization of endobronchial lesions at bronchoscopy or based on clinical-radiological correlation and exclusion of opportunistic infections.RESULTS:The median time from initial presentation with KS to the development of pulmonary involvement was nine months. Dyspnea (79%) and dry cough (79%) were the most common presenting symptoms. Oral palatal involvement was present in 58% of patients with pulmonary KS. Pulmonary nodules (58%) were the most common radiological finding, but an interstitial pattern was noted in 42% of patients. Pleural effusion was present in 39%. Radiological patterns were not static, as 50% of patients with an initial interstitial pattern progressed to develop poorly formed nodules in the peripheral lung fields. Endobronchial lesions were noted on bronchoscopy in 23 patients. A presumptive diagnosis of pulmonary KS was made in 10 patients, with autopsy confirmation in four. Chemotherapy completely resolved symptoms in nine of 25 treated (36%) patients, and a further nine (36%) experienced a significant reduction in symptoms. Radiological improvement was noted in two of the clinical responders. Median survival from the time of diagnosis of pulmonary KS was only eight months, and symptoms relapsed within six weeks of achieving the best clinical response with chemotherapy.CONCLUSIONS:Pulmonary KS presents a difficult diagnostic challenge due to a nonspecific constellation of symptoms and radiological findings. Bronchoscopy is diagnostic when endobronchial lesions are visualized but, more important, it can exclude opportunistic infections. In some patients, even with a negative bronchoscopy, the diagnosis may still be established using clinical-radiographic correlation, particularly if there is radiological evolution to a nodular pattern over time. Multidrug chemotherapeutic regimens appear to have some symptomatic benefit, but radiological improvement is extremely limited. Progression of disease occurs in virtually all patients, and the median survival is only eight months from the point of recognition of pulmonary KS.

Pulmonary Kaposi's sarcoma (KS) occurs in more than 10% of patients with acquired immunodeficiency syndrome (AIDS) and has a high mortality rate. Prompt detection, diagnosis, and treatment reduce patient morbidity and mortality. The objective of this study was to determine the efficacy of 99mTc-hexakis-2-methoxy isobutyl isonitrile (99mTc-MIBI) imaging in detecting pulmonary AIDS-related KS. 99mTc-MIBI imaging was performed on 72 human immunodeficiency virus-seropositive patients with bronchoscopic diagnosis of pulmonary KS (36 patients), pneumonia (22), normal tracheo-bronchial tree (11), lymphoma (2), and bronchogenic carcinoma (1). Lung uptake and lymph node detection in KS were compared on planar and single photon emission computed tomography (SPECT) scans. The lung/myocardium ratios on the 1-h planar images were significantly higher in KS and normal lungs than opportunistic infection. Using the lung/myocardium ratio of 1 as cutoff, the sensitivity, specificity, and accuracy of the 1-h planar images for detecting pulmonary KS were 75, 57.58, and 66.67%, respectively. Abnormal lymph node uptake, pleural/pericardial effusions, and ascites were detected more readily on SPECT. Planar 99mTc-MIBI imaging has moderate sensitivity, specificity, and accuracy for detecting pulmonary KS. SPECT is more effective in detecting abnormal lymph nodes, pleural/pericardial effusions, and ascites. 99mTc-MIBI SPECT followed by planar imaging at 40-60 min can be useful in assessing pulmonary KS.

The cellular quality of the endocervical swab specimen used for the detection of Chlamydia trachomatis may dramatically impact the sensitivity of the diagnostic assay used. An evaluation of the adequacy of 319 endocervical swab specimens from women attending two inner-city sexually transmitted disease and family planning clinics, as well as five high school-based family planning clinics, was performed, and the resulting data were compared with the diagnostic results obtained by both Amplicor PCR and Microtrak direct fluorescent-antibody (DFA) staining. The swab from each patient was rolled across the open circular area of a DFA slide and then used to inoculate a transport tube for PCR (Roche), after which the swab was discarded. The slides were stained and examined by epifluorescence microscopy for the presence of C. trachomatis elementary bodies and for the presence and number of cell types to determine specimen adequacy. Cellular adequacy for a cervical swab specimen was defined as the presence of one or more columnar epithelial or metaplastic epithelial cells or the presence of more than 100 erythrocytes per high-power microscopic field. Of the 319 specimens read by DFA, 204 (63.9%) were determined to be adequate. There were 34 (10.7%) positive specimens by DFA and/or PCR. Twenty-nine (9.1%) specimens were positive by PCR, 20 (6.3%) specimens were DFA positive, and 15 (4.7%) were concordantly positive by both tests. The prevalence of chlamydia among adequate specimens was 14.2% (29/204), compared to 4.3% (5/115) for inadequate specimens (P < 0.0001). Variations in specimen quality and the sensitivity of the diagnostic assay used have a significant impact on determining the prevalence of C. trachomatis in a population.

A new rapid direct immunofluorescence assay, the SimulFluor direct fluorescent-antibody (DFA) assay, which can simultaneously detect herpes simplex virus types 1 and 2 (HSV-1 and -2) and varicella-zoster virus (VZV), was evaluated in comparison with our current standard procedures of (i) shell vial direct immunoperoxidase (shell vial IP) staining and cell culture for detection of HSV and (ii) cytospin DFA staining for VZV detection. A total of 517 vesicular, oral, genital, and skin lesion specimens were tested by all three procedures. For HSV detection, the SimulFluor DFA assay had an overall sensitivity, specificity, positive predictive value, and negative predictive value of 80.0, 98.3, 92.3, and 95.1%, respectively, when compared to culture. Shell vial IP staining had a sensitivity, specificity, positive predictive value, and negative predictive value of 87.6, 100, 100, and 96.9%, respectively, when compared with cell culture. The SimulFluor DFA assay, however, offers same-day, 1.5-hours results versus a 1- to 2-day wait for shell vial IP staining results and a 1- to 6-day wait for culture results for HSV. For VZV detection SimulFluor DFA staining detected 27 positive specimens as compared to 31 by our standard cytospin DFA technique--a correlation of 87.1%. A positive SimulFluor reaction for VZV is indicated by yellow-gold fluorescence compared to the bright apple-green fluorescence observed by cytospin DFA staining. There is no difference in turnaround time between the two assays. The SimulFluor DFA assay is a rapid immunofluorescence assay that can detect 80% of the HSV-positive specimens and 87% of the VZV-positive specimens with a 1.5-h turnaround time.

Kaposi's Sarcoma Presenting with Endobronchial Lesions