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Biomedical subjects

M R Hammerschlag

Publications and source records attributed to M R Hammerschlag.

At least 19 recordsLinked to original sources

Persistent infection with Chlamydia pneumoniae following acute respiratory illness.

Chlamydia pneumoniae is emerging as a significant cause of respiratory disease, including pneumonia and bronchitis, in humans. In this recently completed study of infection due to C. pneumoniae in patients presenting with pneumonia to SUNY Health Science Center at Brooklyn, we identified two individuals for whom cultures were positive on multiple occasions over a 1-year period. To determine the frequency of persistent respiratory infection with C. pneumoniae, follow-up specimens were obtained from nine individuals with culture-documented C. pneumoniae infection. Five of these individuals had persistent infection: four had a flulike illness characterized by pharyngitis, and one had bronchitis with prominent bronchospasm. All five individuals appeared to have acute C. pneumoniae infection as determined by results of serologic tests (titers of IgM antibody for all individuals were greater than or equal to 1:16). For three patients, cultures remained positive for 11 months despite therapy with 10- to 21-day courses of tetracycline or doxycycline. These observations suggest that persistent infection with C. pneumoniae may follow acute infection and may persist for many months. Infection with C. pneumoniae may be very difficult to eradicate with use of currently available antibiotics even if there is a clinical response to therapy.

Acute Disease

In vitro activities of five quinolones against Chlamydia pneumoniae.

The in vitro susceptibilities of 10 strains of Chlamydia pneumoniae were determined for five quinolones, including ciprofloxacin, ofloxacin, fleroxacin, temafloxacin, and sparfloxacin. Sparfloxacin was the most active compound tested, followed by ofloxacin and temafloxacin. Ciprofloxacin and fleroxacin were the least active. The use of HEp-2 cells for testing C. pneumoniae resulted in larger inclusions but essentially the same endpoints as were seen with use of HeLa 229 cells.

Anti-Infective Agents

In vitro activities of azithromycin, clarithromycin, L-ofloxacin, and other antibiotics against Chlamydia pneumoniae.

The in vitro susceptibilities of 11 strains of Chlamydia pneumoniae to azithromycin, clarithromycin, erythromycin, L-oflaxacin, and doxycycline were determined. Clarithromycin was the most active agent tested, with an MIC for 90% of strains and minimal chlamydiacidal concentration for 90% of strains of 0.03 microns/ml. The activity of azithromycin was similar to those of erythromycin and doxycycline, with MICs for 90% of strains of 0.125 to 0.25 microns/ml. However, the prolonged half-life and enhanced tissue penetration of azithromycin should allow for less frequent dosing and shorter duration of therapy than with erythromycin or clarithromycin. L-Ofloxacin had activity similar to that of ofloxacin, with MICs of 0.125 to 0.5 micron/ml. From the results of this in vitro study, azithromycin and clarithromycin appear to be effective antibiotics that may have a role in the treatment of infections due to C. pneumoniae.

Anti-Bacterial Agents

Comparison of a chemiluminometric immunoassay with culture for diagnosis of chlamydial infections in infants.

The performance of Magic Lite (CIBA-Corning), a chemiluminescent immunoassay (CIA), was compared with that of culture for the diagnosis of neonatal chlamydial conjunctivitis and respiratory infection. We performed a retrospective evaluation of 51 ocular and 96 nasopharyngeal specimens previously collected for culture testing with the CIA. The sensitivities for the ocular and the nasopharyngeal specimens were 91 and 91.7%, respectively. The specificities for both sites were 100%. A subsequent prospective study evaluating 71 ocular and 38 nasopharyngeal specimens revealed sensitivities of 83.3 and 20%, respectively. The specificities for both sites were 100%. The CIA performed favorably, compared with culture, for the diagnosis of chlamydial conjunctivitis; however, the CIA appeared less sensitive for the diagnosis of respiratory infection, including pneumonia.

Antigens, Bacterial

Use of HEp-2 cells for improved isolation and passage of Chlamydia pneumoniae.

Chlamydia pneumoniae has proved to be difficult to isolate and propagate in cell culture. We compared the growth of three strains of C. pneumoniae, TW-183 and two clinical isolates from Brooklyn, N.Y., in five cell lines, including HeLa 229, McCoy, HL, HEp-2, and HTED, an immortalized human tracheal cell line. HEp-2 was the most sensitive cell line tested. When 10-fold dilutions of three C. pneumoniae strains at known titers were inoculated into the different cell lines, the mean number of inclusion-forming units per milliliter was 1 to 2 log units higher in the HEp-2 than in the other cell lines. This difference was statistically significant. Omission of pretreatment with DEAE-dextran resulted in larger inclusions than those seen in pretreated cells, with the exception of McCoy and HTED cells. Retrieval of clinical specimens previously cultured on HeLa 229 cells and comparison of mean inclusion counts in fresh clinical specimens simultaneously inoculated on HeLa 229 and HEp-2 cells suggested that culture in HEp-2 cells may require only the initial inoculation and one passage, compared with three to four passages, as required by culture in HeLa 229 cells.

Bacteriological Techniques

Role of Chlamydia pneumoniae in acute chest syndrome of sickle cell disease.

Children with sickle cell disease and acute chest syndrome were investigated for infection with Chlamydia pneumoniae and Mycoplasma pneumoniae. Of 30 patients who had 32 episodes of acute chest syndrome, four (13%) had C. pneumoniae isolated from the nasopharynx; two of these also had serologic evidence of acute infection, and one had positive nasopharyngeal isolates on two subsequent occasions during the course of 1 year with stable, elevated titers of anti-C. pneumoniae IgG, suggesting chronic infection. Two patients with negative cultures had serologic evidence of infection with C. pneumoniae. None of 32 cultures for M. pneumoniae were positive, and although anti-M. pneumoniae IgM developed in two patients, one of these patients had evidence of C. pneumoniae infection (positive culture and seroconversion). We conclude that C. pneumoniae infection is prevalent in our sickle cell population with acute chest syndrome. Until further studies clarify the pathophysiologic significance of C. pneumoniae infection, we believe that early inclusion of erythromycin as antimicrobial therapy for acute chest syndrome seems reasonable.

Adolescent

Infection with Chlamydia pneumoniae in Brooklyn.

Of 91 children and adults with lower respiratory tract infection, 17 (18.7%) had evidence of infection with Chlamydia pneumoniae. Infection was more common in older adolescents and adults than in children. Only 3 of 8 culture-positive patients with paired sera had serologic evidence of acute infection. Two patients were culture positive over a 12-month period. Two other culture-positive patients had evidence of coinfection with other bacterial respiratory tract pathogens, which in these cases appeared to be responsible for the acute episode of pneumonia. Patterns of infection ranged from acute pneumonia to apparent chronic asymptomatic carriage, and there was no characteristic clinical presentation. Studies using cultures in other populations, including asymptomatic individuals, are needed for a better understanding of the epidemiology and clinical relevance of this organism.

Acute Disease

Isolation of Chlamydia pneumoniae from the lungs of patients infected with the human immunodeficiency virus.

Chlamydia pneumoniae is being recognized as a common cause of respiratory tract infections. Bronchoalveolar lavage specimens from human immunodeficiency virus-infected patients were examined by culture for this pathogen. Of 50 specimens examined, 5 (10%) were positive for C. pneumoniae. Four of these (80%) were also positive for other pathogens frequently implicated as causes of respiratory disease in this patient population. C. pneumoniae may frequently inhabit the respiratory tracts of human immunodeficiency virus-infected individuals.

Adult

Asymptomatic respiratory tract infection with Chlamydia pneumoniae TWAR.

Chlamydia pneumoniae is a newly recognized organism associated with respiratory tract infections. Asymptomatic infection with C. pneumoniae, although it has been suggested to occur, has not been previously documented. We describe two asymptomatic individuals infected with this organism; these infections demonstrate that C. pneumoniae is able to establish a subclinical infection.

Antibodies, Bacterial

Chlamydicidal activity of human alveolar macrophages.

Pneumonia due to Chlamydia trachomatis is a disease limited mainly to infants under 6 months of age. Rare cases have been reported in immunocompromised adults. One possible reason for the propensity of the pneumonia to occur in the very young may be related to differences in the phagocytic and bactericidal capacity of alveolar macrophages (AMs) in young infants and adults. At birth a function of AMs is clearance of surfactant-related material from the alveolar surface. Studies in animals have suggested that engorgement of AMs with surfactant-related lipids may reduce the microbicidal capacity of these cells. In the present study we determined that AMs obtained from healthy, nonsmoking adults were capable of killing both human biovars of C. trachomatis, with complete killing observed by 48 h after inoculation. Preincubation of AMs from adults with surfactant did not reduce the capacity of the cells to kill C. trachomatis.

Adult

Comparison of Kodak Surecell Chlamydia Test Kit with culture for the diagnosis of chlamydial conjunctivitis in infants.

The accuracy of the Surecell Chlamydia Test Kit (Kodak Clinical Products, Rochester, N.Y.) in detecting neonatal conjunctival infection caused by Chlamydia trachomatis was determined by comparison of this enzyme immunoassay with the isolation of C. trachomatis in tissue culture. Kodak Surecell is a rapid monoclonal antibody-based membrane capture enzyme immunoassay which can be processed in the office of a physician. The sensitivity and specificity compared to culture in detecting C. trachomatis in conjunctival specimens from infants with conjunctivitis were 93 and 96%, respectively. The test does not require specialized equipment or trained personnel and would be ideal for physicians who see low numbers of infants with possible chlamydial conjunctivitis in their offices.

Antibodies, Monoclonal

Comparison of two enzyme immunoassays to culture for the diagnosis of chlamydial conjunctivitis and respiratory infections in infants.

Data are limited for the performance of enzyme immunoassays for the detection of Chlamydia trachomatis in conjunctival and nasopharyngeal specimens from infants. The only available data are for one assay, Chlamydiazyme (Abbott Diagnostics). The purpose of this study was to compare a new enzyme immunoassay, Pathfinder (Kallestad Diagnostics), with Chlamydiazyme and culture for the diagnosis of chlamydial conjunctivitis and pneumonia in infants. Pathfinder differs from Chlamydiazyme in that it uses a monoclonal antibody directed against the chlamydial lipopolysaccharide in addition to a polyclonal antichlamydial antibody. Triplicate conjunctival and nasopharyngeal specimens were obtained from 97 infants with conjunctivitis, and additional nasopharyngeal specimens were obtained from 14 infants with suspected chlamydial pneumonia (total, 111 nasopharyngeal specimens). Twenty-nine (30%) of the conjunctival specimens from infants with conjunctivitis and four (28.6%) of the nasopharyngeal specimens from the infants with pneumonia were positive for C. trachomatis by cell culture. The sensitivities, specificities, and positive and negative predictive values for Pathfinder for conjunctival specimens were 96.6, 98.5, 96.6, and 98.5%, respectively. The results for Chlamydiazyme were 96.6, 100, 100, and 98.6%, respectively. For nasopharyngeal specimens, the results for Pathfinder were 77.8, 94.6, 73.7, and 95.7%, respectively. The results for Chlamydiazyme were 66.7, 95.7, 75, and 93%, respectively. Pathfinder and Chlamydiazyme appeared to perform equivalently for the detection of C. trachomatis in both eye and nasopharyngeal specimens from infants with chlamydial conjunctivitis and pneumonia.

Antibodies, Monoclonal

Efficacy of neonatal ocular prophylaxis for the prevention of chlamydial and gonococcal conjunctivitis.

Opinions differ concerning the efficacy of prophylaxis against neonatal chlamydial and gonococcal conjunctivitis. From January 1986 through June 1988, we gave all infants born at Kings County Hospital Medical Center one of three prophylactic agents -- silver nitrate drops, erythromycin ophthalmic ointment, or tetracycline ophthalmic ointment. The treatments were rotated monthly. Gonococcal ophthalmia occurred in 8 of the 12,431 infants born during the study (0.06 percent), 1 in the silver nitrate group, 4 in the erythromycin group, and 3 in the tetracycline group (P not significant). Seven of these infants were born to women who had received no prenatal care. From September 1985 through December 1987, we screened 4357 pregnant women for cervical chlamydial infection, of whom 341 (8 percent) had positive cultures. Of their offspring, 230 were evaluated for neonatal chlamydial conjunctivitis; the incidence was 20 percent in the silver nitrate group, 14 percent in the erythromycin group, and 11 percent in the tetracycline group (P not significant). We conclude that neonatal ocular prophylaxis with either erythromycin or tetracycline ophthalmic ointment does not significantly reduce the incidence of chlamydial conjunctivitis in the offspring of mothers with chlamydial infection as compared with silver nitrate, and that better management of maternal chlamydial infection is therefore required. We also conclude that there is a small but appreciable incidence of neonatal gonococcal ophthalmia that could be prevented by better prenatal screening and treatment of maternal gonococcal infection.

Chlamydia Infections

Herpes zoster in an adult recipient of live attenuated varicella vaccine.

A healthy 30-y-old female physician who was immunized with two doses of live attenuated varicella vaccine developed a localized case of zoster involving the right T8-10 dermatomes 36 mo after vaccination. The virus isolated from her rash was an unusual wild-type of varicella-zoster virus. After immunization she developed detectable antibodies to varicella-zoster virus, but antibodies were no longer detectable after 20 mo. Six months before development of zoster, she was exposed to a patient with varicella; however, she did not develop a clinical illness although she again became seropositive. To date, this is the only reported case of zoster among 187 healthy adult vaccinees.

Adult