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PubMedDate not supplied

Investigations on the role of some viral, chlamydian, rickettsian and mycoplasmic agents in several gynecological diseases.

This work presents the results of a study on some viral, chlamydial, rickettsial and mycoplasmal agents incidence and their role on several gynecological ailments: vulvovaginitis, cervicitis, cervicovaginitis. The presence of some viral, chlamydial, rickettsial and mycoplasmal antigens in the vaginal secretion was investigated by immunofluorescence technique, isolation on selective media for Mycoplasma, and MGG staining in a group of 60 women with gynecopathies (group A) and in a control group (also 60 clinically healthy women) (group B). This study pointed out to higher incidence of chlamydial and mycoplasma antigens as well as of parainfluenza virus types I and III, adenovirus and herpes virus type II in group A. The serological screening revealed significant differences between the specific antibodies to antigens found in vaginal secretions to prove the presence of an immunological response on the same category of subjects.

Antibodies, Bacterial↗
PubMed1977

Laboratory-acquired Rocky Mountain spotted fever. The hazard of aerosol transmission.

Nine patients with laboratory-acquired Rocky Mountain spotted fever were seen during the period 1971 to 1976. Investigation of each case revealed either definite or probable exposure to an aerosol containing infectious rickettsiae; in no case was there evidence of parenteral exposure either by accidental self-inoculation or by tick bite. These illnesses are believed to represent infection acquired via the respiratory route. This report emphasizes the aerosol hazard of Rickettsia rickettsii in the laboratory and discusses the possibility of respiratory transmission of Rocky Mountain spotted fever in nature. The illness occurred only in personnel who had received either no vaccination or the primary series of the commercial (Lederie) vaccine against this infection. Other personnel who had received the primary series with multiple booster vaccinations demonstrated increased immunity as measured by humoral antibody titers and rickettsial antigen-induced lymphocyte transformation; no cases of clinical disease developed in these multiply-vaccinated personnel.

Adult↗
PubMed2006

Isolation of Rickettsia rickettsii and Rickettsia bellii in cell culture from the tick Amblyomma aureolatum in Brazil.

Brazilian spotted fever (BSF) is a highly lethal disease caused by Rickettsia rickettsii. In the present study, rickettsial infection was evaluated in 669 Amblyomma aureolatum adult ticks collected from naturally infested dogs in Taiaçupeba, a BSF-endemic area in the state of São Paulo. Ten (1.49%) ticks were infected with Rickettsia bellii, and 6 (0.89%) ticks were infected with R. rickettsii. Both Rickettsia species were isolated and established in Vero cell cultures. The Rickettsia isolates were characterized by molecular analyses, sequencing fragments of different rickettsial genes. Our results suggest that A. aureolatum is an important vector of R. rickettsii in Brazil.

Animals↗
PubMedDate not supplied

[Immunohistochemical diagnosis of Mediterranean spotted fever: detection of rickettsial antigens in the initial skin lesions].

In eight patients with Mediterranean spotted fever we evaluated the yield of the direct immunofluorescence technique against rickettsial antigens for the early laboratory diagnosis of the disease. Frozen sections of biopsy specimens of the initial lesion (tache noire) taken on the admission day were processed by a fluorescent conjugate reactive against Rickettsia conorii. In seven cases, coccobacillary formations consistent with rickettsiae were observed in the studied specimens. The results were negative in the controls and in three of six samples of exanthema elements obtained from six simultaneously studied patients with Mediterranean spotted fever. Our data demonstrate the diagnostic value of direct immunofluorescence applied on the tache noire. This technique is particularly useful in the initial stages of the disease, before the clinical and serological features have completely developed.

Adult↗
PubMed1975

The pathologic findings in rickettsial pneumonia.

A fatal case of Q fever pneumonia with demonstration of the organisms in the lungs is presented. The disease clinically simulates bacterial lobar pneumonia. Neutrophils were conspicuously absent in the inflammatory process. Histiocytes predominated in the alveolar septal spaces and produced both radiologically and pathologically an alevolar infiltrate. Histiocytic hyperplasia and focal necrosis were present. Histiocytes similar to those seen in the alveolar spaces of the lungs distorted the normal architecture of the lymph nodes. In scattered areas necrosis with histiocytes palisading in the periphery simulating the lesions of cat-scratch disease and tularemia were seen.

Adult↗
PubMed2003

[Rudolf Stefan Weigl--scientist and human being].

Rudolf Stefan Weigl died in 1957, 45 years ago. This year we are celebrating 120 anniversary of his birthday. He was a great Polish scientist who led research on Rickettsia prowazeki and epidemic typhus. R. Weigl developed a method of R. prowazeki culture in louse gut and elaborated the technology of epidemic typhus vaccine production. He and his co-workers introduced first vaccination of medical staff, people from endemic area in Poland and missionaries working in Asia. He was an international authority on prophylactics and control of rickettsial epidemic typhus.

Disease Outbreaks↗
PubMed1983

Correlation of rickettsial titers, circulating endotoxin, and clinical features in Rocky Mountain spotted fever.

Blood rickettsial titers, skin biopsy results, and circulating endotoxin measurements were correlated with the clinical course of disease in patients with Rocky Mountain spotted fever (RMSF). Nine of 11 patients with documented RMSF had Rickettsia rickettsii isolated from plasma samples. Of the eight patients in whom rickettsial titers were measured, seven had 10(0.7) to 10(1.2) median tissue culture infective doses (TCID50) per milliliter; all seven had mild to moderately severe disease. One patient with fulminant, fatal untreated RMSF had 10(3) TCID50/mL of postmortem plasma. Two patients from whom rickettsiae were not isolated had positive direct immunofluorescent stains of skin biopsy material for R rickettsii. Circulating endotoxin was present in two patients, one with documented rickettsemia and one with a positive skin biopsy alone. Only low levels of circulating rickettsiae are present in patients with moderately severe disease. Measurement of plasma endotoxin is not useful in the early diagnosis of RMSF.

Adolescent↗
PubMed1989

Serotypes in Cowdria ruminantium and their relationship with Ehrlichia phagocytophila determined by immunofluorescence.

Two tick-borne rickettsial pathogens of ruminants, Cowdria ruminantium (causative agent of heartwater disease) and Ehrlichia phagocytophila (causative agent of tick-borne fever), were successfully cultivated in caprine or ovine neutrophilic granulocytes. Infected cultures were subsequently used as antigens in the indirect fluorescent antibody test. Low-level bilateral serological cross-reactions could be detected between Cowdria and Ehrlichia. In addition, comparison of five Cowdria stocks using immunofluorescence demonstrated the existence of distinct serotypes within the genus of Cowdria. It is concluded that the occurrence of these serotypes will considerably complicate the current serodiagnosis of heartwater.

Animals↗
PubMed1993

Atypical pneumonias. Clinical and extrapulmonary features of Chlamydia, Mycoplasma, and Legionella infections.

Pneumonias caused by atypical organisms usually have extra-pulmonary features. Chlamydial pneumonia often starts with hoarseness and fever, and respiratory tract symptoms may not appear for days. Mycoplasmal pneumonia may manifest with ear pain and a nonproductive cough. Legionnaires' disease presents with high fevers and central nervous system and gastrointestinal abnormalities. Diagnosis of chlamydial infection is accomplished with serologic testing. Patients are unresponsive to erythromycin treatment and should be started on empirical doxycycline (Doryx, Vibramycin) therapy. The presence of cold agglutinins in the appropriate clinical setting permits a presumptive diagnosis of mycoplasmal infection. Clinical diagnosis of Legionella pneumonia may be made in patients with pneumonia who also have relative bradycardia with elevated serum transaminases or hypophosphatemia with gastrointestinal or central nervous system symptoms. Erythromycin is the mainstay of treatment of legionnaires' disease, but treatment failures have been reported. Doxycycline is less expensive, has a better safety profile, and is better tolerated than erythromycin.

Anti-Bacterial Agents↗
PubMed1998

Purification of Cowdria ruminantium organisms for use in genome analysis by pulsed-field gel electrophoresis.

Cowdria ruminantium is an obligate intracellular rickettsial pathogen which is responsible for a tick-borne disease of domestic and wild ruminants called heartwater or cowdriosis. Although several genes have been cloned and partially sequenced, the genome size, gross structure, and organization of the C. ruminantium genome is unknown. Genome analysis of the organism has been hindered because it is difficult to obtain C. ruminantium DNA free from contaminating host cell DNA, and this probably accounts for the lack of genome size data for this organism. In this study we investigated several methods for purifying C. ruminantium from bovine cellular contaminants and organisms of a relatively high purity were obtained. These were used to prepare Cowdria DNA which was analyzed by pulsed-field gel electrophoresis (PFGE) and which revealed a genome approximately 1900 kbp in length plus an additional extra-chromosomal fragment migrating with an apparent size of 815 kbp. This is the first time that the genome size of C. ruminantium has been determined and the first demonstration of an extrachromosomal element.

Animals↗
PubMed2005

Human granulocytic anaplasmosis and Anaplasma phagocytophilum.

Human granulocytic anaplasmosis is a tickborne rickettsial infection of neutrophils caused by Anaplasma phagocytophilum. The human disease was first identified in 1990, although the pathogen was defined as a veterinary agent in 1932. Since 1990, US cases have markedly increased, and infections are now recognized in Europe. A high international seroprevalence suggests infection is widespread but unrecognized. The niche for A. phagocytophilum, the neutrophil, indicates that the pathogen has unique adaptations and pathogenetic mechanisms. Intensive study has demonstrated interactions with host-cell signal transduction and possibly eukaryotic transcription. This interaction leads to permutations of neutrophil function and could permit immunopathologic changes, severe disease, and opportunistic infections. More study is needed to define the immunology and pathogenetic mechanisms and to understand why severe disease develops in some persons and why some animals become long-term permissive reservoir hosts.

Anaplasma phagocytophilum↗
PubMed1999

The tetracyclines.

The tetracyclines, among the first of the antibiotics to become available 50 years ago, remain widely used. Tetracyclines have bacteriostatic activity against a wide variety of pathogens that are responsible for many common and some exotic infections. They are particularly valuable in the treatment of atypical pneumonia syndromes, chlamydial genital infections, rickettsial infection (Rocky Mountain spotted fever, typhus, Q fever), Lyme disease, and ehrlichiosis. On the basis of pharmacokinetic considerations, doxycycline is the preferred agent among the tetracycline congeners. Minocycline may have a limited role in the treatment of methicillin-resistant staphylococcal disease in situations in which an oral antimicrobial agent may be appropriate. The tetracyclines are generally contraindicated during pregnancy and childhood because of their association with dental staining and interference with bone growth. Photosensitivity may occur with some tetracyclines, and several drug and food interactions may limit gastrointestinal absorption.

Contraindications↗