Epidermal Growth Factor Receptor Activating Mutations in Squamous Histology of Lung Cancer Patients of Southern Bulgaria.

UNLABELLED: There is only limited data on the prevalence of epidermal growth factor receptor (EGFR) activating mutations in squamous cell carcinomas and adenosquamous carcinomas of the lung in patients of the Southern Bulgarian region and the efficacy of EGFR tyrosine kinase inhibitors. AIM: Previous reports for Bulgarian population showed high incidence of EGFR mutations in the squamous cell carcinomas, so we set the goal to investigate their frequency in Southern Bulgaria, after precise immunohistochemical verification of lung cancers. MATERIALS AND METHODS: Two hundred and thirty-six lung carcinomas were included in this prospective study. All biopsies were initially analysed with p63, TTF1, Napsin A, CK7, CK34ßE12, synaptophysin, CK20 and CDX2. Two hundred and twenty-five non-small cell lung carcinomas were studied with real-time PCR technology to assess the status of the EGFR gene. RESULTS: We detected 132 adenocarcinomas (58.7%), 89 squamous cell carcinomas (39.2%), 4 adenosquamous carcinomas (1.8%), 9 large cell neuroendocrine carcinomas (3.8%) and 2 metastatic colorectal adenocarcinomas (0.8%). Activating mutations in the EGF receptor had 3 out of 89 squamous cell carcinomas (3.37%). We have established mutations in L858R, deletion in exon 19 and rare mutation in S7681. One out of four adenosquamous carcinomas had a point mutation in the L858R (25%). CONCLUSIONS: The frequency of EGFR mutations we found in lung squamous cell carcinomas in a Southern Bulgarian region is lower than that in European countries. Ethnic diversity in the region does not play role of an independent predictive factor in terms of mutation frequency.

Specific prophylaxis of enzootic chlamydial ovine abortion.

A vaccine against chlamydial ovine abortion was prepared according to an original method and experimentally applied to more than 500,000 animals in large breeding units. The vaccine induced a considerable seroconversion (as demonstrated by complement fixation tests) and reduced by 3--5 times the damage due to chlamydioses. Vaccination of primiparous ewes, followed by 2--3 annual revaccinations, gave good results, conferring resistance on the vaccinated animals.

Prevalence of mycoplasma in the genital tract of pregnant women. Preliminary data.

The prevalence of Myoplasma hominis and "T" strains was investigated in 175 pregnant women in the 12th--40th week of pregnancy. It was possible to isolate the "T" strain from 30.3%, M. hominis from 11.4% and both strains from 9.7% of the women.

An antigen for the diagnosis of M. pneumoniae infections by passive hemagglutination.

The authors establish the optimal conditions (protein concentration, temperature) for the coupling of purified mycoplasma antigen to sheep red blood cells, in order to obtain an antigenic complex stable for at least 1 year. This comples allows specific determination by passive hemagglutination--a simple and rapid technique--of anti-mycoplasma antibodies in the sera of men or animals suspected of mycoplasma infections. Under the stated experimental conditions, antibody titers equal to or higher than 1/128 indicate an infection with M. pneumoniae.

Prevalence of chlamydial infections in male patients with nongonococcal urethritis.

Direct examination of urethral smears made evident the presence of chlamydial infection in 162 (38.1%) of 425 male patients with nongonococcal urethritis. Serum antibodies to the group antigen could be detected by complement fixation and microagglutination reactions only in about 50% of the cases with chlamydial infection. The proportion of chlamydial strains isolated in chick embryos was rather low (14.8%) and the isolation rate appeared to correlate with the abundance of urethral secretion.

Mycoplasma pneumoniae infection detected by immunofluorescence in patients with certain skin diseases.

The presence of Mycoplasma pneumoniae and/or herpes antigens was investigated by indirect immunofluorescence (IF) reactions in exfoliated cells or biopsy specimens from 43 patients with different skin diseases (treatment-resistant cutaneous herpes, genital herpes, acne, urticaria, dermatitis, erythema multiforme, ecthyma contagiosum). Either M. pneumoniae or herpes antigen could be detected in 21 (55.26%) and 12 (31.57%) of the 38 IF-positive cases, respectively, while the associated occurrence of mycoplasma and herpes antigens was observed in 5 (13.15%) of the patients.

Contribution of the rapid viral diagnosis by immunofluorescence to the choice of therapy in uveitis cases.

Viral and inframicrobial antigens were detected by immunofluorescence (IF) in exfoliated conjunctival and corneal cells from 22 patients with uveitis, 2-9 different antigens being simultaneously visualized in 17 of the cases. The treatment applied on the ground of the etiological diagnosis specified by IF reactions consisted in the administration of tetracycline, Flumidin (Virustat), standard gamma-globulin or specific antiherpes immunoglobulin, the NIVGRIP inactivated influenza vaccine. This therapy led to persistent recovery (coincident with the disappearance of the antigens from conjunctival cells) in 15 cases and to clinical improvement in 7 cases. The importance of the rapid viral diagnosis by IF for the choice of an adequate therapy of uveitis is discussed.

Study of antibodies against viruses, chlamydiae, rickettsiae and Mycoplasma pneumoniae in children with respiratory diseases.

Seroconversion to different viral, chlamydial, rickettsial and mycoplasma antigens was followed up in 134 children aged 0-6 years, hospitalized with different respiratory diseases. Parainfluenza viruses type 1, 2 and 3 and adenoviruses appeared to be involved in the etiology of most of the cases; respiratory syncytial virus was often found to play a role in pneumonia/bronchopneumonia and in "influenza-like illness", while chlamydiae and M. pneumoniae could be incriminated in cases of "influenza-like illness", as well as in the other categories of respiratory disease. Mixed infections with the agents studied could be detected.

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.

Preliminary investigations on the diagnostic value of passive hemagglutination and complement fixation tests in infections with Mycoplasma pneumoniae.

In order to evaluate the efficiency of passive hemagglutination (PHA) and complement fixation (CF) tests for the diagnosis of M. pneumoniae infections, 144 serum samples--out of which 81 from patients with respiratory and cutaneous infections and 63 from subjects with other diseases (controls)--were comparatively investigated by the two methods. The PHA test made evident a positivity index of 65% in the case of mixed pneumonias, as against 17% in controls, while the results obtained by CF were almost identical in the two groups investigated. The high specificity and sensitivity of the PHA reaction recommend this method for the diagnosis of acute M. pneumoniae infections.

Rapid detection by immunofluorescence of multiple viral infections in patients with keratitis.

The presence of 12 viral (herpes 1 and 2, influenza A(H1N1), A(H3N2) and B, parainfluenza 1, 2, 3, adenovirus 5) and inframicrobial (Chlamydia, mycoplasma, Rickettsia burneti) antigens was investigated by direct or indirect immunofluorescence (IF) reactions in exfoliated conjunctival cells from 110 patients with nonbacterial keratitis and keratoconjunctivitis. A rapid etiological diagnosis could be obtained in 101 (92%) of the cases, parainfluenza and herpes antigens being the most frequently detected. In most of the cases the simultaneous presence of several antigens was made evident. Encouraging results were obtained by the application of a specific treatment based on the diagnosis provided by the IF reaction.

Multiple viral and inframicrobial infections detected by immunofluorescence reaction in exfoliated cells from patients with eye or respiratory diseases.

The presence of viral (herpes 1 and 2, influenza A and B, parainfluenza 1, 2, and 3, adenovirus) and inframicrobial (Chlamydia, R. burneti and mycoplasma) antigens was investigated by indirect immunofluorescence reaction in exfoliated cells from 107 patients with chronic eye diseases and 77 patients with chronic respiratory diseases. Single or associated viral or inframicrobial antigens were detected in 80% of the former and in 60% of the latter patients. The proportion of multiple infections was of about 60% in both patient groups.

Passive hemagglutination and complement fixation reactions in the early diagnosis of Mycoplasma pneumoniae infections.

Complement fixation (CF) and passive hemagglutination (PHA) tests (the latter with a M. pneumoniae antigen coupled by glutaraldehyde onto red blood cells) were performed in 263 patients with various infectious diseases (mostly in the 1st and 2nd week after onset) and non-infectious ones. CF reaction proved to be inappropriate for the early etiological diagnosis of mycoplasma infections, since the high titers were distributed undifferentially among the various patient groups and many sera (38%) showed anticomplementary activity. A PHA titer of at least 1/128 (preferably of 1/512) points to the presence of a M. pneumoniae infection, especially if clinical, radiological and laboratory data suggest a nonbacterial or mixed pneumonia. The diagnosis is often early enough to orientate the etiological therapy towards macrolides and tetracyclines. The PHA reaction recommended is specific, sensitive, reproducible and easy to perform.