Pneumocystis jirovecii colonisation in HIV-positive and HIV-negative subjects in Cameroon.

OBJECTIVE: To determine the prevalence of Pneumocystis pneumonia (PCP), a major opportunistic infection in AIDS patients in Europe and the USA, in Cameroon. MATERIALS AND METHODS: Induced sputum samples from 237 patients without pulmonary symptoms (126 HIV-positive and 111 HIV-negative outpatients) treated at a regional hospital in Cameroon were examined for the prevalence of Pneumocystis jirovecii by specific nested polymerase chain reaction (nPCR) and staining methods. CD4 counts and the history of antiretroviral therapy of the subjects were obtained through the ESOPE database system. RESULTS AND CONCLUSION: Seventy-five of 237 study participants (31.6%) were colonised with Pneumocystis, but none showed active PCP. The Pneumocystis colonisation rate in HIV-positive subjects was more than double that of HIV-negative subjects (42.9% vs. 18.9%, P < 0.001). In the HIV-positive group, the colonisation rate corresponds to the reduction in the CD4 lymphocyte counts. Subjects with CD4 counts >500 cells/µl were colonised at a rate of 20.0%, subjects with CD4 counts between 200 and 500 cells/µl of 42.5%, and subjects with CD4 counts <200 cells/µl of 57.1%. Colonisation with Pneumocystis in Cameroon seems to be comparable to rates found in Western Europe. Prophylactic and therapeutic measures against Pneumocystis should be taken into account in HIV care in western Africa.

Ciprofloxacin reduces the risk of hemolytic uremic syndrome in patients with Escherichia coli O104:H4-associated diarrhea.

BACKGROUND: Whether antibiotic treatment in patients with enterohemorrhagic Escherichia coli (EHEC)-associated diarrhea influences the risk of hemolytic uremic syndrome (HUS) has still to be elucidated. PATIENTS AND METHODS: During the EHEC epidemic which occurred in northern Germany in spring 2011, 24 patients with E. coli O104:H4 infection were treated at our hospitals, 19 of whom developed HUS. The use of antibiotics before and after the onset of HUS was documented, and the outcome in patients with and without antibiotic treatment was evaluated. RESULTS: Of the 24 patients with EHEC-associated diarrhea, seven received antibiotics before any signs of HUS were present (ciprofloxacin, cefotaxime, amoxicillin and/or metronidazole). Four of these seven patients (57 %) and 15 of the 17 patients (88 %) who were treated without antibiotics developed HUS (p = 0.12). Microbiological testing showed all E. coli O104:H4 to be extended-spectrum beta lactamase producers and thus susceptible only to fluoroquinolones, aminoglycosides and carbapenems. Two of the five patients (40 %) treated with ciprofloxacin and 17 of the 19 patients (89 %) treated without ciprofloxacin developed HUS (p = 0.043). CONCLUSION: In our E. coli O104:H4-infected patients, treatment of diarrhea with antibiotics did not increase the risk of HUS. Significantly fewer patients treated with ciprofloxacin developed HUS than patients who did not receive ciprofloxacin.

High prevalence of Pneumocystis jirovecii colonization among patients with autoimmune inflammatory diseases and corticosteroid therapy.

BACKGROUND: Patients with autoimmune inflammatory diseases (AID) account for 13-36% of Pneumocystis pneumonia (PCP) cases in human immunodeficiency virus (HIV)-negative patients. Up to 88% of PCP cases in HIV-negative patients are associated with prior steroid treatment. Pulmonary colonization with Pneumocystis in HIV-negative patients is associated with corticosteroid therapy in up to 75% of cases. The aim of this study was to detect the prevalence and risk factors of pulmonary colonization with Pneumocystis jirovecii in patients with AID receiving corticosteroid therapy in comparison with healthy control persons. METHODS: We investigated induced sputa of 102 patients with AID on current corticosteroid treatment and of 117 healthy controls for the presence of P. jirovecii using polymerase chain reaction (PCR). RESULTS: Twenty-nine patients (28.5%) with AID were colonized with P. jirovecii compared to three healthy controls (2.6%) [p < 0.001, odds ratio (OR) 15.10, 95% confidence interval (CI) 4.43-51.38]. In patients with AID, age over 60 years was significantly associated with colonization (p = 0.015, OR 3.19, 95% CI 1.27-7.94). Multivariate analysis showed age to be independently associated with the colonization of P. jirovecii (95% CI 1.002-1.092). Neither duration nor dose of corticosteroid therapy nor immunosuppressive co-medication had a significant influence on P. jirovecii colonization. CONCLUSION: Patients with AID, especially those over 60 years of age, display a high prevalence of colonization with P. jirovecii. Clinicians should be aware of this and ensure that they consider the possibility of PCP when pulmonary symptoms arise in these patients.

Pneumocystis species in Brown Leghorn laying hens--a hint for an extra-mammalian reservoir.

The fungus Pneumocystis spp. causes Pneumocystis pneumonia in immunocompromised mammals including humans, whereas healthy individuals are often colonized and can transmit it to others. There is little evidence that Pneumocystis spp. is also present outside mammalian species. We describe the first detection of Pneumocystis DNA from the lungs and air sacs of laying hens from deep litter and floor husbandry systems. The DNA from chickens' lungs and air sacs was amplified with a Pneumocystis-specific mtLSU rRNA gene nested PCR and sequenced. Pneumocystis DNA was detected in 20 of 111 (18.0%) hens. The DNA sequences showed specific differences to all known Pneumocystis mtLSU sequences. In induced sputum samples of 2 of 7 farm workers at this poultry farm, human Pneumocystis jirovecii strains without these mutations were detected; therefore, a transmission between chickens and farm workers appears implausible.

[Main virulence factors in Escherichia coli isolates from swine over two weeks old with edema disease and/or E. coli diarrhea]. / Hauptvirulenzfaktoren bei Escherichia coli-Isolaten von über zwei Wochen alten Schweinen mit Odemkrankheit und/oder Colidiarrhöe.

The OK antigens and the fimbriae F4 of E. coli with haemolysis isolated from 113 cases of oedema disease and/or diarrhoea were identified serologically. The genes for F18 and for enterotoxins LT, STIa and STII as well as Shigatoxin Stx2e were determined by PCR. Fimbrial variants F18ab and F18ac were distinguished by means of indirect immunofluorescence on smears prepared from the intestinal mucosa and from cultures grown under appropriate conditions. Adhesive fimbriae were detected with every case or isolate, respectively, by means of at least one out of the techniques mentioned above. The serogroup O149:K91 with fimbriae F4ac (K88ac) and genes for the enterotoxins LT and STII was most prevalent. Serogroup O139:K12 with fimbriae F18ab and the gene for Stx2e was second, whereas serogroups O141ab and O141ac with fimbriae F18ac and genes for Stx2e, STII and often LT were much less prevalent. The serogroup O147:K89 with fimbriae F18ac, and genes for STIa and STII was detected for the first time in Switzerland.

[Vaccinations in patients with immunodeficiency or immunosuppressive therapy]. / Impfen bei Immundefekten oder medikamentöser Immunsuppression.

Patients with immunodeficiency and patients under immunosuppressive therapy have an increased risk of infectious diseases. Vaccination strategies are needed to protect them from preventable diseases. The underlying disease and severity of the immune impairment may have influence on indications and contra-indications of vaccines. Inactivated vaccines can be administered safely according to the current recommendations of the Permanent Commission on Vaccinations of the Robert-Koch-Institut in Berlin, Germany (STIKO). Depending on the severity of the immune dysfunction, antibody response to vaccinations varies. Where possible, the antibody response following vaccinations should be tested. Previously, attenuated live vaccines were considered to be strictly contra-indicated in immunocompromised patients. Today, the administration of attenuated live vaccines is thought to be possible, depending on the degree and type of immunodeficiency or immunosuppression of the individual.

Hepatitis B and C: neglected diseases among health care workers in Cameroon.

BACKGROUND: Healthcare workers (HCW) are at risk of acquiring blood-borne viral infections, particularly hepatitis B (HBV), hepatitis C (HCV), and HIV, especially in high endemic regions such as sub-Saharan Africa. METHODS: Sera from 237 hospital workers in Southwest Cameroon were tested for anti-hepatitis B core antigen (anti-HBc), hepatitis B surface antigen (HBsAg), anti-hepatitis B surface antigen (anti-HBs), anti-HCV and (on a voluntary basis) for anti-HIV. Information on pre-study testing for HBV, HCV and HIV and pre-study HBV vaccination status was collected from these individuals. RESULTS: The pre-study testing rate among participating hospital staff for HBV was 23.6% (56/237), for HCV 16% (38/237), and for HIV 91.6% (217/237). The pre-study HBV vaccination rate was 12.3% (29/237). Analysis of anti-HBc revealed that 73.4% (174/237) of the hospital staff had been infected by HBV. Active HBV infection (HBsAg positivity) was detected in 15 participants. Anti-HCV was found in four of 237 participants, HIV antibodies were detected in four of 200 participants tested. CONCLUSION: HBV and HCV are neglected diseases among HCW in sub-Saharan Africa. The vaccination rate against HBV was very low at 12.3%, and therefore anti-HBc testing should be mandatory to identify HCW requiring HBV vaccination. Testing for HBV and routine HBV vaccination for HBV-negative HCW should be strongly enforced in Cameroon.

Safety and immunogenicity of a trivalent single dose seasonal influenza vaccine containing pandemic A(H1N1) antigen in younger and elderly subjects: a phase III open-label single-arm study.

BACKGROUND: During the pandemic of the 2009 A(H1N1) influenza virus strain, 20-40% of the population in some areas were infected. Infection with A(H1N1) may be mild, with an average case fatality rate below 0.25%, but severe disease is not limited to patients with underlying medical conditions. Since A(H1N1) is expected to continue to circulate it is included in the seasonal influenza vaccines for the 2010-2011 winter season. We investigated the immunogenicity and safety of a preservative-free non-adjuvanted seasonal trivalent influenza vaccine. METHODS: We conducted a single center single-arm study involving 142 subjects (77 adults of 18-60 years and 65 subjects 61 years and above) to test the immunogenicity, safety, and tolerability of a trivalent split influenza vaccine. The vaccine contained 15µg of hemagglutinin of each of the virus strains recommended for the 2010-2011 northern hemisphere winter season (A/California/7/2009 (H1N1)-like strain; A/Perth/16/2009 (H3N2)-like strain; B/Brisbane/60/2008-like strain) in a non-adjuvanted preservative-free formulation. Antibody response to each antigen was measured by hemagglutination inhibition (HI) 21 days after immunization. Subject diary cards and additional telephone interviews were used to assess the safety profile. RESULTS: By day 21 after the vaccination, seroconversion, or a 4-fold antibody increase in HI antibody titers, was detectable against A(H1N1) in 84% and 75% of younger and older adults, against A(H3N2) in 80% and 57%, and against the B influenza strain in 61% and 33%. HI antibody titers of 40 or more were observed against A(H1N1) in 99% and 90% of younger and older adults, against A(H3N2) in 100% and 90%, and against the B influenza strain in 91% and 78%. Pre-vaccination antibody titers were protective against A(H1N1), A(H3N2), and B in 26%, 44% and 33%, respectively of the adults below 61 years and in 27%, 54% and 44% of the subjects of 61 years and above. Local and systemic reactions were more common in younger than in older subjects and the most frequently reported reactions were pain at the injection site (36%), myalgia (24%), and fatigue (15%). Five percent elderly subjects and 1% of younger subjects had mild or moderate unsolicited adverse events such as prolonged ecchymosis or night sweats that resolved within 7 days after vaccination. CONCLUSIONS: This single dose trivalent seasonal influenza vaccine generated protective antibodies to all three viral strains and had an acceptable safety profile in both younger and older adults (ClinicalTrials.gov identifier: NCT01147081).

Degradation of pyrene at low defined oxygen concentrations by a Mycobacterium sp.

In a fermentor, a Mycobacterium sp. was grown on pyrene at defined oxygen concentrations in a range from 11.4 to 227 microM. The maximal growth rate (mumax = 0.057 h-1) and the dissolved oxygen half-saturation constant (KDO = 5.9 microM) were calculated. At 3.4 microM, the growth rate (mu = 0.011 h-1) was only half of what was expected from the kinetic data. Apparently, this was due to limitation of an oxygenase of pyrene degradation.

Nitrogen Fixation in Continuous Culture with NH(4)Cl-Containing Media.

N balance and N dilution were determined from growth of Azospirillum brasilense Sp7 and two unidentified gram-negative nitrogen-fixing microorganisms in continuous culture supplied with NH(4)Cl. At the 1.1 and 2.2 mM NH(4)Cl steady states (N-to-C ratios of 1:68 and 1:34, respectively), the organisms grew with NH(4)Cl and N(2) as N sources simultaneously under carbon limitation. No ammonium could be detected in the supernatant of these cultures.

[Incidence and significance of humoral antibodies in females with recurrent spontaneous abortions]. / Auftreten und Bedeutung humoraler Antikörper bei Frauen mit wiederholten Spontanaborten.

Serum samples from 70 patients with two or more early spontaneous abortions and, for comparison, sera from 20 healthy and fertile women were assayed by indirect immunofluorescence for the presence of antibodies to sperms and genital organ antigens and for non-organ specific and organ specific antibodies. All sera were tested for thyreoglobulin antibodies by hemagglutination. The frequency of sperm antibodies and autoantibodies was significantly higher in patients with recurrent abortions than in the control group. There was no relation between the type or titer of antibodies and the clinical data of the patients.

Degradation of phenanthrene, fluorene, fluoranthene, and pyrene by a Mycobacterium sp.

Mycobacterium sp. strain BB1 was isolated from a former coal gasification site. It was able to utilize phenanthrene, pyrene, and fluoranthene as sole sources of carbon and energy and to degrade fluorene cometabolically. Exponential growth with solid phenanthrene, pyrene, and fluoranthene was obtained in fermentor cultures. The growth rates were 0.069, 0.056, and 0.040 h-1, respectively. Several metabolites of phenanthrene and fluorene metabolism were identified.

Air pollution and allergy: experimental studies on modulation of allergen release from pollen by air pollutants.

The fact that allergic diseases increase in prevalence is a generally accepted and worldwide phenomenon. The causes for this increase are not known: only hypothetical concepts exist. Epidemiological studies comparing Eastern and Western European populations have shown a striking difference in the prevalence of respiratory atopic diseases, which is lower in the East. At the same time, different patterns of air pollution have been described, namely 'classical' type I, characterized by SO2 and dust prevailing in the East, and 'modern' type II, characterized by organic compounds, fine particles and ozone, which is more prominent in the West. Type II was associated in multivariate regression analysis with increased prevalence of IgE-mediated allergy. Pollen grains collected from industrial regions with high polyaromatic hydrocarbon load in West Germany, but not in East Germany, were shown to be agglomerated with airborne particles. In vitro exposure of pollen to particles indicated morphological changes and increased allergen release from the pollen. In vitro exposure of pollen to gaseous pollutants (SO2 and NO2) under different conditions of humidity resulted in SO2-induced, but not NO2-induced reduction of allergen release from pollen. It is concluded that the bioavailability of grass pollen allergens may be modulated by air pollutants, supporting the concept of an interaction between pollen and pollutants in the atmosphere outside the organism which in turn may affect allergy-relevant phenomena.