Bacterial adhesion to biological versus polymer prosthetic materials used in abdominal wall defect repair: do these meshes show any differences in vitro?

PURPOSE: Although clinical data suggest the similar performance of collagen-based biological prosthetic materials to some polymer materials, the use of a biomesh for abdominal hernia repair in a setting of infection is controversial. This in vitro study compares the adhesion of two Staphylococcus strains to polymer and biological meshes. METHODS: Sterile fragments of Optilene(®) (Op), Surgipro™ (Surg), Preclude(®) (Precl), TIGR(®) (TIGR), Bio-A(®) (BioA), Permacol™ (Perm), Surgisis(®) (SIS), and Tutomesh(®) (Tuto) were inoculated with 10(6) CFU of S. aureus (Sa) or S. epidermidis (Se) (n = 18 per strain per mesh). The first five meshes are polymer materials while Perm, SIS and Tuto are biomeshes. After 24/48 h of incubation, bacterial adhesion was examined by sonication, scanning electron microscopy (SEM) and light microscopy. RESULTS: Sa and Se showed a high affinity for the absorbable meshes (TIGR, BioA, Perm, SIS, Tuto) (p < 0.001). Precl yielded the lowest bacterial loads (p < 0.001). Surg, Precl and BioA underwent no substantial change over time, while Op (p < 0.001) and TIGR (p < 0.05) showed decreasing bacterial loads during incubation. The Sa-contaminated biomeshes behaved similarly while biomeshes inoculated with Se returned higher bacterial yields at 48 h, especially SIS (p < 0.001). SEM and light microscopy observations revealed planktonic bacteria and biofilms on the polymer surface and bacterial niches in biomesh pores. CONCLUSIONS: Within 48 h of contamination, the absorbable polymer and biological meshes exhibited high bacterial loads. Given their lower affinity for both bacterial strains, the conventional non-absorbable polymer materials could be better candidates for use in contaminated surgical fields.

Viral infections of the central nervous system in Spain: a prospective study.

The aim of the study was to determine the incidence of viruses causing aseptic meningitis, meningoencephalitis, and encephalitis in Spain. This was a prospective study, in collaboration with 17 Spanish hospitals, including 581 cases (CSF from all and sera from 280): meningitis (340), meningoencephalitis (91), encephalitis (76), febrile syndrome (7), other neurological disorders (32), and 35 cases without clinical information. CSF were assayed by PCR for enterovirus (EV), herpesvirus (herpes simplex [HSV], varicella-zoster [VZV], cytomegalovirus [CMV], Epstein-Barr [EBV], and human herpes virus-6 [HHV-6]), mumps (MV), Toscana virus (TOSV), adenovirus (HAdV), lymphocytic choriomeningitis virus (LCMV), West Nile virus (WNV), and rabies. Serology was undertaken when methodology was available. Amongst meningitis cases, 57.1% were characterized; EV was the most frequent (76.8%), followed by VZV (10.3%) and HSV (3.1%; HSV-1: 1.6%; HSV-2: 1.0%, HSV non-typed: 0.5%). Cases due to CMV, EBV, HHV-6, MV, TOSV, HAdV, and LCMV were also detected. For meningoencephalitis, 40.7% of cases were diagnosed, HSV-1 (43.2%) and VZV (27.0%) being the most frequent agents, while cases associated with HSV-2, EV, CMV, MV, and LCMV were also detected. For encephalitis, 27.6% of cases were caused by HSV-1 (71.4%), VZV (19.1%), or EV (9.5%). Other positive neurological syndromes included cerebellitis (EV and HAdV), seizures (HSV), demyelinating disease (HSV-1 and HHV-6), myelopathy (VZV), and polyradiculoneuritis (HSV). No rabies or WNV cases were identified. EVs are the most frequent cause of meningitis, as is HSV for meningoencephalitis and encephalitis. A significant number of cases (42.9% meningitis, 59.3% meningoencephalitis, 72.4% encephalitis) still have no etiological diagnosis.

The seroprevalence of human infection with Rickettsia slovaca, in an area of northern Spain.

An epidemiological survey was undertaken to explore human exposure to Rickettsia slovaca in two provinces of northern Spain. When IFAT were used to test 200 members of the general population for antibodies to rickettsiae of the spotted-fever group, six (3.3%) were found positive, presumably, since Dermacentor is one of the most common genera of human-biting tick in the study area, for antibodies to R. slovaca. Thirty-one (16.9%) of an additional 183 subjects who presented shortly after being bitten by ticks were also found seropositive. The difference in seroprevalence between the general and the tick-bitten populations was significant. Subject gender had no influence on seroprevalence in either population, although, in the tick-bitten group, age and occupation did have a significant influence on the prevalence recorded. Immunoblotting was used to confirm the presence of antibodies in the five subjects, all from the tick-bitten group, found to have acute infections. Three D. marginatus ticks obtained from three of these acute cases were found PCR-positive for R. slovaca DNA.

Epidemiological study of Rickettsia typhi infection in two provinces of the north of Spain: analysis of sera from the general population and sheep.

Data relating to Rickettsia typhi infection in Spain are scarce. A serological survey of 383 serum samples (184 males, 199 females) from the general population and 120 sera from sheep were studied by immunofluorescence assay (IFA). The human serum samples were collected from the general population of Palencia and Burgos provinces, and sheep serum samples were collected from Palencia province. Of the 383 human serum samples studied, 29 were positive for antibodies against R. typhi (7.5%) No statistical differences were found according to age, sex, origin (rural vs. urban) or geographic distribution, but a significant difference was observed related to occupation. In addition, 69 serums were found positives for R. typhi in sheep samples (57.5%). Our results indicated the circulation of R. typhi infectious for humans and sheep in Palencia and Burgos provinces. This study indicates that sheep may be infected with R. typhi, and that animals can, therefore be used as indicators of the presence of this organism.

A sero-epidemiological study of Rickettsia typhi infection in dogs from Soria province, central Spain.

Data relating to Rickettsia typhi infection in Spain are scarce. The seroprevalence of canine infection with this species has now been investigated, in dogs from the central province of Soria. The results of indirect immunofluorescence assays indicated that nine (12.3%) of the 73 dogs checked were carrying antibodies against R. typhi. The gender, age and breed of the dog, and whether it was used for hunting, shepherding, guarding or simply as a pet, apparently had no significant affect on the probability of it being seropositive. Being infested with fleas or having a history of such infestation was, however, significantly associated with seropositivity. The present results confirm that dogs may be infected with R. typhi and indicate their potential usefulness as sentinels in epidemiological studies of the pathogen. The results of wide-scale, serological studies of dogs may allow the geographical distribution of R. typhi to be mapped relatively simply.

Serological study of hantavirus in man in the Autonomous Community of Madrid, Spain.

Data relating to hantavirus infection in Spain are scarce and limited to rural areas. The aim of this work was to study the seroprevalence of hantavirus infection in the Autonomous Community of Madrid (ACM), a region containing both rural and urban populations in different ecological settings. Sera from 3852 individuals (1849 male, 2003 female) were screened by indirect inmunofluorescence, with Vero E6 cells infected with Puumala, Hantaan and Seoul viruses as antigens. Screen-positive results were confirmed by Western blot with recombinant Seoul virus nucleocapsid protein as antigen. Antibodies against hantavirus were detected in 12 sera (0.31%). No statistical differences were found according to sex and age. The highest prevalence was found in the southeastern area, significantly higher than the central and north-western areas. The most frequent serological pattern was reactivity against all three viruses used (33.3% of all positive sera). Therefore, this study confirms the presence of hantavirus infection in the ACM, including for the first time an urban area of Spain, but with the highest prevalence in a rural area. Serological evidence suggests that there is more than one circulating serotype.

Prevalence of antibodies to Rickettsia typhi in an area of the center of Spain.

It was the aim of the present work to evaluate Rickettsia typhi antibody prevalence in 'Comunidad Autónoma de Madrid' (CAM), an area in the centre of Spain. A total of 640 serum samples from the general population were tested by an indirect immunofluorescence assay. Specific R. typhi antibodies were found in 44 (6.8%) of the samples. The present survey results demonstrate the occurrence of R. typhi human infections in this area.

Effect of pH and buffer system on the in-vitro activity of five antifungals against yeasts.

We have compared the effect of various media on the in-vitro activity of amphotericin B, flucytosine, fluconazole, itraconazole and ketoconazole against 93 clinical yeast isolates by a micro-broth dilution technique. The media used were: RPMI 1640 with 2% glucose, buffered with 0.165 M MOPS at pH 7.0; the same medium, but buffered at pH 7.4; and the same medium, but buffered at pH 7.4 with 0.15% sodium bicarbonate. The three media gave similar results with azole antifungals and flucytosine, but the medium buffered at pH 7.0 failed to detect different populations of yeasts with respect to amphotericin B susceptibility. In the case of the media buffered at pH 7.4, Candida krusei was significantly less susceptible to amphotericin B than Candida albicans or Torulopsis glabrata. We could not evaluate the results obtained with Candida parapsilosis and Cryptococcus neoformans since these species did not grow adequately in all three media.

[Hantavirus infection in Spain: seroepidemiologic study in the province of Soria]. / Infección por Hantavirus en España: estudio seroepidemiológico en la provincia de Soria.

BACKGROUND: The aim of the present was to study the seroprevalence of Hantavirus infection in the province of Soria, Spain. METHODS: Total specific antibodies against Hantavirus (Hantaan and Puumala virus) were studied by indirect immunofluorescence in 537 sera (251 males and 286 females) of a population from the province of Soria, distributed proportionally to the number of inhabitants from the health care areas. The age range of the population was from 1 to 95 years, the group mode ranging between 25 to 30 years and with a mean age of 36.4 years. The sera with antibody titers equal to or higher than 1/32 were considered as positive. RESULTS: Significant titers of antibodies against Hantaan or Puumala virus were detected in 2.2% of the total of sera studied (12 positive sera); 1.75% in women (5/286) and 2.8% in men (7/251). Of these 12 positive sera, 8 reacted against both virus (1.5%-8/537), 3 exclusively to Puumala and 1 only to Hantaan. Seroprevalence against Puumala was 2% (11/537) and 1.7% against Hantaan (9/537). The age of the subjects with positive sera ranged from 3 to 73 years with a mean of 33.8 years with higher prevalence in the group from 30 to 40 years of age (4.1%). CONCLUSIONS: The results of this study confirm the existence of infection by Hantavirus in Spain.

Cutaneous tuberculosis: a clinical, histopathologic, and bacteriologic study.

BACKGROUND: In recent years cutaneous infections with Mycobacterium tuberculosis with an atypical clinical appearance have become more common because of the increasing number of immunocompromised patients. OBJECTIVE: We report the clinical, histopathologic, and bacteriologic data of 11 patients with several forms of cutaneous tuberculosis seen during the past 14 years. METHODS: Patients from whom M. tuberculosis was isolated from culture of skin biopsy specimens, sinus drainage, or material aspirated from cutaneous abscesses were included. In all but two patients a biopsy specimen was obtained for histopathologic study. All but one patient received combined antituberculous therapy. RESULTS: The clinical diagnoses were scrofuloderma (four cases), cutaneous miliary tuberculosis (two), lupus vulgaris (two), tuberculous gumma (two), and one unclassified. All but three patients had evidence of either previous or simultaneous tuberculous foci other than in the skin. Histopathologic findings varied according to the type of cutaneous tuberculosis. CONCLUSION: In some patients with cutaneous tuberculosis, lesions are atypical in appearance because of immunodeficiency. Culture for M. tuberculosis should be performed in all suspected cases, even in those in whom special stains for acid-fast bacilli are negative.

Problems in minimum inhibitory concentration determinations in coryneform organisms. Comparison of an agar dilution and the Etest.

The antimicrobial susceptibility of 159 coryneform organisms was determined by an agar dilution and Etest methods. Overall, the correlation between minimum inhibitory concentrations obtained by both techniques was good (> or = 0.09) for most antibiotics and organisms although the essential agreement ranged from 59% to 88.3%. Most organisms were equally categorized (sensitive, intermediate, or resistant) by both methods with only 0.2%, 0.4%, and 3.5% of very major, major or minor discrepancies, respectively. Such percentages dropped significantly when discrepant strains were retested. The correlation was specially good for Corynebacterium jeikeium and Corynebacterium urealyticum.

Development of myelopathy before herpes zoster rash in a patient with AIDS.

We describe the case of a patient with AIDS who developed progressive myelopathy due to varicella-zoster virus 2 months before the appearance of skin lesions typical of herpes zoster. Varicella-zoster virus was isolated from his CSF. Therapy with acyclovir failed to control his neurological complications despite its in vitro efficacy against the isolates.

[Incidence of tuberculostatic-resistant Mycobacterium tuberculosis. Clinical aspects and impact on therapy and clinical course]. / Incidencia de Mycobacterium tuberculosis resistente a tuberculostáticos. Aspectos clínicos e impacto sobre la terapia y evolución.

BACKGROUND: To know the incidence of Mycobacterium tuberculosis resistant to anti-tuberculin drugs in addition to the clinical features, treatment and evolution of the patients. METHODS: This was a retrospective study of the clinical histories of patients with isolation of Mycobacterium tuberculosis with some type of resistance studied from January 1980 to April 1992. RESULTS: During the period studied 470 patients were diagnosed with tuberculosis by cultures. In 30 of these cases (6.4%) Mycobacterium tuberculosis resistant to Isoniazide (8), Streptomycin (6), Isoniazide + Rifampicin (4), Isoniazide + Streptomycin (3), Isoniazide + Ethambutol (2), Isoniazide + Rifampicin + Streptomycin (2), Isoniazide + Rifampicin + Ethambutol (2), Rifampicin (1), Ethambutol (1), Isoniazide + Pyrazinamide (1) and Isoniazide + Rifampicin + Streptomycin + Ethambutol (1) were isolated. Clinical information was obtained on 23 patients, with the most frequent clinical pictures being those of respiratory infection (15). Five cases occurred in HIV+ patients. The resistance was considered as primary in 58.97% of the cases with modifications in empiric treatment being necessary in 6 cases. In 15 out of the 19 patients from whom the data of the follow up was obtained the evolution was good. CONCLUSIONS: Resistance to Mycobacterium tuberculosis was 6.4%, with the high number of strains resistant to Rifampicin being of note. In 79% of the cases in which follow up data was obtained the resistance had no impact on treatment due to the good evolution of the patients in relation with the treatment used.

Cytopathic effect mimicking virus culture due to Mycobacterium tuberculosis.

Mycobacterium tuberculosis grew, from a bronchoalveolar lavage of a patient with AIDS, on a gentamicin-supplemented cell culture monolayer, causing a focal and slowly spreading cytopathic effect resembling that of a virological isolate. The same effect was observed after inoculation of two different inocula of M. tuberculosis onto the same cell culture.

[Mycobacteriosis during 1980-1990 in a Madrid hospital]. / Micobacteriosis durante el período 1980-1990 en un hospital de Madrid.

BACKGROUND: To assess the incidence and features of environmental mycobacteria that can produce disease over a ten years period (1980-1990) in an University Hospital from Madrid (Spain). METHODS: Medical records of all patients in whom and environmental mycobacteria that can produce disease had been isolated were reviewed and classified as definite, possible or not clinically significant isolates, according to clinical features and microbiologic findings. RESULTS: Mycobacterium species were isolated in 415 patients (491 clinical samples over a total of 3003, 16.3%). In 29 patients a environmental mycobacteria that can produce disease was identified. Medical records from 25 patients were retrieved, being this mycobacteria isolated classified as with definite clinical significance in 8 cases, with possible clinical significance in 4, and without clinical significance in 13 cases. Clinical features in the significant cases were: lung infection (3 cases), pleural and pericardial disease (1 case), peritonitis (1) and soft tissue infection (1) Two patients died. Surgical excision of the lesion was performed in the remaining patients, and clinical cure was achieved in five cases. CONCLUSIONS: The most prevalent mycobacterial infection in our environment is still due to M. tuberculosis infection, followed by M.avium-intracellulare. Surgical treatment is a valid approach in patients with localized infection by environmental mycobacteria that can produce diseases.

[Isolation of Mycobacterium tuberculosis with primary resistance to chemotherapeutic agents in patients with HIV infection]. / Aislamiento de Mycobacterium tuberculosis con resistencia primaria a quimioterápicos en pacientes con infección por VIH.

BACKGROUND: To evaluate the resistance of Mycobacterium tuberculosis in subjects with simultaneous infection by the human immunodeficiency virus. METHODS: Isolation of Mycobacterium tuberculosis was carried out in a University hospital over a period of 7 years with selection of those corresponding to subjects with HIV infection. The isolation of Mycobacterium tuberculosis with resistance to one or more chemotherapeutic drugs was identified and is described herein. RESULTS: A total of 287 subjects were identified having tuberculous disease, 39 (13.59%) of them presented a simultaneous infection by the human immunodeficiency virus. In 4 of the latter (10.26%) Mycobacterium tuberculosis resistant to one or more chemotherapeutic drugs was isolated with the most frequent resistance being to isoniazide (3/4). CONCLUSIONS: A high degree of diagnostic suspicion must be maintained in patients with the human immunodeficiency virus with respect to tuberculosis, not only because of frequent endogenous activation but also because of the danger of in-hospital transmission. The possibility of resistance makes systematic antibiograms in these cases advisable. In these patients recommendations regarding treatment should be followed avoiding shortened or simplified therapeutic periods which have occasionally been demonstrated as ineffective.

PIP: A retrospective study of drug resistance of Mycobacterium tuberculosis in patients simultaneously affected by tuberculosis (TB) and HIV was conducted in a Spanish university hospital. 39 of the 287 patients (13.6%) were also HIV seropositive. Mycobacterium tuberculosis with primary resistance to at least one of the major antitubercular drugs was isolated in 4 of the 39 (10.3%). The 4 patients (3 males, 1 female) demonstrating primary drug resistance were intravenous drug users aged 23-30 years. 3 were resistant to isoniazid, 1 to rifampin, 1 to streptomycin, and 1 to pyrazinamide. None was resistant to ethambutol. 2 were resistant to one drug and 2 were resistant to 2 drugs. Resistance to streptomycin in 1 patient may have been secondary to treatment with aminoglucosides for endocarditis. It is recommended that diagnostic suspicion of TB be maintained in management of HIV infected patients because of the possibility of drug resistance and of in-hospital transmission. Shortened or simplified treatment regimens should be avoided in seropositive patients.