Corrélation Entre La Consommation D'Antibiotiques Et Les Taux D'Antibiorésistance Chez P. Æruginosa Dans Un Service De Réanimation Des Brûlés Tunisien: Étude Sur 6 Ans (2014-2019).

Antibiotics are one of the greatest advances in modern medicine. Antibiotic resistance is one of the most serious threats to global health, aggravating the prognosis of immunocompromised patients, especially burn patients. Our objective was to study the consumption of antibiotics of critical importance according to the WHO and the correlation between antibiotic resistance in Pseudomonas æruginosa and the consumption of these antibiotics. Our study took place in the Medical Laboratory in collaboration with the Trauma and Burn Center's Burn Unit in Tunisia. In our retrospective study, 1384 non-repetitive strains of Pseudomonas æruginosa responsible for colonization or infection were included, between January 2012 and December 2019. Pseudomonas æruginosa was the most isolated bacterial strain in the service, with an average rate of 15.9% of the service's bacterial ecology. The antibiotic resistance rates tested were high: 77.1% to piperacillin-tazobactam, 56% to ceftazidime, 74.9% to imipenem, 78.8% to amikacin, 54.7% to ciprofloxacin and 32.8% to fosfomycin. Among our strains, 81.8% were multi drug-resistant strains. The analysis of the correlation between the level of consumption of antibiotics and the antibiotic resistance levels in Pseudomonas æruginosa showed that the increased consumption of piperacillin-tazobactam increased resistance not only to piperacillin-tazobactam but also to imipenem and amikacin as well as multi drug resistance. Similarly, the increase in the consumption of fosfomycin correlates with resistance to piperacillin-tazobactam and imipenem.

Campylobacter fetus Meningitis: A diagnosis to suggest in immunocompromised patients.

Campylobacter fetus causes in humans mostly gastroenteritis. Systemic infection occurs almost exclusively in immunocompromised patients with chronic debilitating diseases. We report the case of a Campylobacter fetus meningitis in a woman aged 48 years with a history of systemic lupus erythematosus treated with corticosteroids and immunosuppressive drugs. Cerebrospinal fluid culture was positive for Campylobacter fetus. The evolution was favorable using imipenem and ciprofloxacin.

Lymphatic spread in an immunocompetent adult.

Cutaneous tuberculosis with lymphatic spread is rarely described. We report the case of a woman aged 38, immunocompetent, working in a fruit sorting center, who consulted us for ulceration of the left third finger that had persisted for four months, following a prick from a prickly pear. Physical examination revealed a nodular, erythematous, and ulcerative lesion of the left third finger, associated with inflammatory subcutaneous nodules arranged in a line along the ipsilateral upper extremity and an ipsilateral axillary lymph node. Laboratory tests and chest X-ray were normal. Pathological examination revealed granulomatous chronic inflammation without necrosis. PCR detected DNA from Mycobacterium tuberculosis. No extracutaneous tuberculosis locations were detected. A tuberculous chancre by direct inoculation was therefore diagnosed. The patient received quadruple therapy (rifampicin + isoniazid + pyrazinamide + ethambutol) for 2 months, followed by a combination therapy based on isoniazid and rifampicin for 6 months. Marked regression of the cutaneous lesions occurred after 1 month of first-line therapy. A tuberculous chancre is a rare form of cutaneous tuberculosis, with possible lymphatic spread, in immunocompromised patients but also in immunocompetent children and young adults.

Increased levels of soluble HLA-G molecules in Tunisian patients with chronic hepatitis B infection.

Hepatitis B virus (HBV) infection is a global health problem. The mechanisms of immune tolerance in HBV infection are still unclear. The host immune response plays a critical role in determining the outcome of HBV infection. Human leucocyte antigen-G (HLA-G) is involved in immunotolerogenic process and infectious diseases. This study aimed to explore the implication of soluble HLA-G (sHLA-G) and its isoforms in HBV infection. Total sHLA-G (including shedding HLA-G1 and HLA-G5) was analysed by ELISA in 95 chronic HBV patients, 83 spontaneously resolvers and 100 healthy controls (HC). To explore the presence of sHLA-G dimers, we performed an immunoprecipitation and a Western blot analysis on positive samples for sHLA-G in ELISA. The serum levels of sHLA-G were significantly increased in patients with chronic HBV patients compared to spontaneously resolvers and HC (P<.0001). Interestingly, we found an increased level of sHLA-G1 in chronic HBV patients than in spontaneously resolvers and HC (P<.001). In addition, the expression of HLA-G5 seems to be higher in the sera of chronic HBV patients than spontaneously resolvers (P=.026). The analysis of HLA-G dimers showed the presence of homodimers in 93% of chronic HBV patients, 67% in spontaneously resolvers and 60% in HC. These results provide evidence that sHLA-G may have a crucial role in the outcome of HBV infection and could be proposed as a biomarker for infection outcome. Based on its tolerogenic function, HLA-G might be considered as a new promising immunotherapeutic approach to treat the chronic infection with HBV.

[Seroprevalence of human parvovirus B19 in children with fever and rash in the North of Tunisia]. / Prévalence de l'infection par le parvovirus B19 humain au cours des éruptions fébriles de l'enfant dans le Nord tunisien.

The aim of the study is to evaluate the prevalence of specific antibodies anti-human parvovirus B19 (PVB19) immunoglobulin M (IgM) and IgG in children with fever and rash. This study involved 257 children aged from 7 months to 15 years with febrile rash unrelated to measles and rubella (seronegative for IgM). The sera were examined by immunoenzymatic assay. Detection of antibodies of PVB19 was done by enzyme-linked immunosorbent assay (Elisa). In our study, prevalence of immunoglobulin G (IgG) and IgM were 44 and 11.3%, respectively. Clinically, children with positive IgM serology had submitted an erythema infectiosum (13/29 cases), myocarditis (1 case), encephalitis (1 case), severe sickle cell anemia (7 cases), and immunocompromised (7 cases). The incidence rate of viral infection was 11.3%; most of the cases of PVB19 infection occurred between the months of May and August. Incidence was higher in the 10-15 years age group (21%). The prevalence of IgG antibody varied and increased with age, it rises from 38.2% in preschool children (19 months-4 years) to 53.5% in those aged between 4.5 and 15 years, reaching 58% in the 10-15 years age group. The four risk factors of PVB19 infection are: (1) those aged between 4.5 and 9 years, which is the most affected age group (P = 0.0018); (2) female gender in children aged between 19 months and 4 years (P = 0.037); (3) transfusion and (4) immune deficiency (P = 0.022 and P = 0.001, respectively). The study of the prevalence of PVB19 infection shows that viral infection is acquired early in childhood, increases with age; viral transmission is favored by the community life. Because of the widespread vaccination program against measles and rubella, the systematic search of PVB19 in front of eruptive fevers becomes important.

HLA-E polymorphism and soluble HLA-E plasma levels in chronic hepatitis B patients.

Chronic hepatitis B virus (HBV) infection occurs in association to a deregulation of immune system. Human leukocyte antigen E (HLA-E) is an immune-tolerant nonclassical HLA class I molecule that could be involved in HBV progression. To measure soluble (s) HLA-E in patients with chronic HBV hepatitis (CHB). We tested the potential association of HLA-E*01:01/01:03 A > G gene polymorphism to CHB. Our cohort consisted of 93 Tunisian CHB patients (stratified in CHB with high HBV DNA levels and CHB with low HBV DNA levels) and 245 healthy donors. Plasma sHLA-E was determined using enzyme-linked immunosorbent assay (ELISA). Genotyping was performed using polymerase chain reaction sequence-specific primer. No association between HLA-E*01:01/01:03 A > G polymorphism and HBV DNA levels in CHB patients was found. G/G genotype is less frequent in CHB patients without significance. sHLA-E is significantly enhanced in CHB patients compared with healthy controls (P = 0.0017). Stratification according to HBV DNA levels showed that CHB patients with low HBV DNA levels have higher sHLA-E levels compared with CHB patients with high HBV DNA levels. CHB patients with G/G genotype have enhanced sHLA-E levels compared with other genotypes (P = 0.037). This significant difference is maintained only for CHB women concerning G/G genotypes (P = 0.042). Finally, we reported enhanced sHLA-E in CHB patients with advanced stages of fibrosis (P = 0.032). We demonstrate, for the first time, the association of sHLA-E to CHB. Owing to the positive correlation of HLA-E*01:01/01:03 A > G polymorphism and the association of sHLA-E to advanced fibrosis stages, HLA-E could be a powerful predictor for CHB progression. Further investigations will be required to substantiate HLA-E role as a putative clinical biomarker of CHB.

Identification of clinically relevant Corynebacterium strains by Api Coryne, MALDI-TOF-mass spectrometry and molecular approaches.

We evaluated the Bruker Biotyper matrix-assisted laser desorption ionization-time of flight (MALDI-TOF) mass spectrometry (MS) for the identification of 97 Corynebacterium clinical in comparison to identification strains by Api Coryne and MALDI-TOF-MS using 16S rRNA gene and hypervariable region of rpoB genes sequencing as a reference method. C. striatum was the predominant species isolated followed by C. amycolatum. There was an agreement between Api Coryne strips and MALDI-TOF-MS identification in 88.65% of cases. MALDI-TOF-MS was unable to differentiate C. aurimucosum from C. minutissimum and C. minutissimum from C. singulare but reliably identify 92 of 97 (94.84%) strains. Two strains remained incompletely identified to the species level by MALDI-TOF-MS and molecular approaches. They belonged to Cellulomonas and Pseudoclavibacter genus. In conclusion, MALDI-TOF-MS is a rapid and reliable method for the identification of Corynebacterium species. However, some limits have been noted and have to be resolved by the application of molecular methods.

[Analysis of severe Legionellosis hospitalized in intensive care units in Tunisia]. / Analyse des cas de légionellose grave hospitalisés dans les services de réanimation en Tunisie.

This study is the first one that describes the situation of Legionnaires' disease (LD) in Tunisia, with its clinical and epidemiological characteristics and investigates the risk factors associated with Legionella infections in our country. We conducted a retrospective multicentric study during 5 years (2008-2012) concerning all confirmed LD cases in Tunisia and we investigated risk factors for infection. The total of confirmed LD cases was 14. Incidence was 0.03. Mean age: 53.1, sex ratio (M/F): 2.6. Summer-autumnal peak was noted. Risk factors for infection were: the great humidity at home (n=4), living in community (n=3) and practice ablutions (before prayer) in public places (n=4). Community acquired legionellosis (n=9) and nosocomial (n=2). Pulmonary symptoms (n=11)+/-gastrointestinal (n=6) and/or neurological signs (n=4). Beta lactams therapy failed (n=11). CXR showed bilateral lesions (n=6). Abnormalities in laboratory values were noted: hyponatremia (n=9), high CPK levels (n=9). Diagnosis was confirmed by positive urinary Legionella antigens test (n=10) and by direct immunofluorescence (n=1). Treatment was based on bitherapy (n=10). Five patients died. The incidence of LD appears lower than other countries. Some risk factors, as ablutions, are different from that reported in Western countries and seem to be specific to our society. Given the seriousness of its consequences, it is strongly recommended to improve the national surveillance system up and register LD as notifiable disease.

Age- and gender-specific effects on VDR gene polymorphisms and risk of the development of multiple sclerosis in Tunisians: a preliminary study.

The vitamin D receptor (VDR) polymorphisms have been reported to be associated with multiple sclerosis (MS); however, evidence remains conflicting. In this report, we investigated the association between two single nucleotide polymorphisms (SNPs) TaqI and ApaI of VDR gene and risk development of MS. TaqI and ApaI SNPs were detected by PCR-RFLP from the DNA of 60 Tunisian patients with MS and 114 healthy controls. Our results show a significant difference of the allelic frequency distribution between the case and control groups for TaqI SNP (P = 0.01), but genotype frequencies were not significantly different (P = 0.07 and 0.23). When adjusting frequency distribution of different alleles and genotypes by age, we found that the difference between the T allele frequencies of this SNP in the group of patients age [15-24] in comparison with the control group of the same age group was statistically significant (P = 0.026). Moreover, frequency of the T allele was significantly higher in male patients compared with controls of the same sex (P = 0.017). However, neither the genotype nor the allele frequency distribution was significantly different between the MS and control populations for the ApaI SNP. Our preliminary results indicate that VDR gene polymorphism could be associated with susceptibility to MS. The role of VDR gene polymorphism should be further studied in other large populations, and the distribution of other polymorphism, such as FokI and BsmI, should be also analysed to confirm another susceptibility polymorphisms gene for MS and to obtain more adequate strategies for treatment of MS.

[Profile and susceptibility to antibiotics in urinary tract infections in children and newborns from 2012 to 2013: Data from 1879 urine cultures]. / Profil et sensibilité aux antibiotiques de 1879 bactéries urinaires pathogènes isolées chez l'enfant (2012-2013).

INTRODUCTION: We present recent data on the bacteriological profile and antibiotic susceptibility of uropathogenic bacteria isolated in children and newborns in our region over the past 2 years. MATERIALS AND METHODS: A retrospective study on the positive urine cultures from pediatric and neonatal populations during 2012-2013. Bacteria were identified using conventional methods. Susceptibility testing was performed and interpreted as recommended by the committee of the susceptibility of the French Society of Microbiology (CA-SFM). RESULTS: We collected 1879 non-redundant bacteria with more than 73% Escherichia coli. Children and infants (mean age, 32 months [range, 1 month to 14 years]) accounted for 84% of the bacteria collected and newborns (mean age, 12 days [range, 1 day to 1 month]) 16%. A female predominance was observed in the pediatric population (M:F sex ratio, 3.2), whereas for the neonatal population, the proportions were almost identical in both sexes (M:F sex ratio, 1.1). Most of the positive urine cultures (n=1234) were from the community. Hospitalized patients (n=636) were divided into pediatric (60%) and neonatal units (40%). Five bacterial genera dominated the bacteriological profile: E. coli, Klebsiella sp., Proteus sp., Enterobacter sp., and Enterococcus. The susceptibility of the main BUP antibiotics used for treatment of frequent UTI showed the effectiveness of furadoine, imipenem, fosfomycin, and colistin. Amoxicillin kept constant activity against Enterococcus and Streptococcus agalactiae. The rates of resistance of Enterobacteriaceae to beta-lactam antibiotics were high, especially in the neonatal population. The production of extended-spectrum beta-lactamase (ESBL) was noted in 12.8% of pediatric Enterobacteria vs. 22.6% of the neonatal strains. For community Enterobacteriaceae, the activity of beta-lactam antibiotics was limited with 11.2% resistance to third-generation cephalosporins (C3G), including 8.6% ESBL production. CONCLUSION: The impact of widespread use of beta-lactam antibiotics in neonatal and pediatric environments is felt. Colistin, imipenem, and fosfomycin are the most frequently used antibiotics active against bacteria responsible for neonatal and pediatric UTI; however, they cannot be used as probabilistic treatment. Nitrofurans seem to be active antibiotics on UTI, but they present limits in their use in neonatal and pediatric populations. Their indication in case of pyelonephritis should be discussed.

Molecular characterization of extended spectrum beta-lactamases produced by Klebsiella pneumoniae clinical strains from a Tunisian Hospital.

OBJECTIVES: Extended-spectrum ß-lactamases are widespread in hospital settings worldwide. The prevalence of ESBL producing Klebsiella pneumoniae (ESBL-KP) strains isolated from patients has recently increased in Tunisia. We conducted this study to determine the prevalence and the genetic characterization of ESBL-KP in a Tunisian Hospital. PATIENTS AND METHODS: We performed antibiotic susceptibility testing, multiplex PCR, and DNA sequencing analysis on 118 non repetitive K. pneumonia strains isolated during three years, to determine the prevalence and genotypes of ESBL among K. pneumoniae clinical isolates. RESULTS: Most ESBL-producing K. pneumonia strains were isolated from hospitalized patients, especially in neonatal and pediatric wards. The resistance to other antibiotics was high. Most of the pathogens were isolated from the urinary tract (86.44%). Carbapenems were the most effective antimicrobial agents followed by amikacin and fosfomycin. The rate of blaSHV, blaTEM, and blaCTX-M genes among the isolates was 89, 56.78, and 81.35%, respectively. Sequencing revealed the amplicons encoding TEM-1, TEM-53, TEM-158, SHV-1, SHV-11, SHV-28, CTX-M-15, CTX-M-15-like. The blaCTX-M-15 was the dominant gene among Tunisian isolates, but this was the first report of blaTEM-53 and blaTEM-158 genes in the country. CONCLUSIONS: Our results confirm the predominance of CTX-M-15 in Tunisia. To our knowledge, this is the first report of TEM-158 and TEM-53 in Tunisia.

Association of an HLA-G 14-bp Insertion/Deletion polymorphism with high HBV replication in chronic hepatitis.

Identification of an HLA-G 14-bp Insertion/Deletion (Ins/Del) polymorphism at the 3' untranslated region of HLA-G revealed its importance in HLA-G mRNA stability and HLA-G protein level variation. We evaluated the association between the HLA-G 14-bp Ins/Del polymorphism in patients with chronic Hepatitis B virus (HBV) infection in a case-control study. Genomic DNA was extracted from 263 patients with chronic HBV hepatitis and 246 control subjects and was examined for the HLA-G 14-bp Ins/Del polymorphism by PCR. The polymorphic variants were genotyped in chronic HBV seropositive cases stratified according to HBV DNA levels, fibrosis stages and in a control population. There was no statistical significant association between the 14-bp Ins/Del polymorphism and increased susceptibility to HBV infection neither for alleles (P = 0.09) nor for genotypes (P = 0.18). The stratification of HBV patients based on HBV DNA levels revealed an association between the 14-bp Ins/Del polymorphism and an enhanced HBV activity with high HBV DNA levels. In particular, the Ins allele was significantly associated with high HBV DNA levels (P = 0.0024, OR = 1.71, 95% CI 1.2-2.4). The genotype Ins/Ins was associated with a 2.5-fold (95% CI, 1.29-4.88) increased risk of susceptibility to high HBV replication compared with the Del/Del and Ins/Del genotypes. This susceptibility is linked to the presence of two Ins alleles. No association was observed between the 14-bp Ins/Del polymorphism and fibrosis stage of HBV infection. We observed an association between the 14-bp Ins/Del polymorphism and high HBV replication characterized by high HBV DNA levels in chronic HBV patients. These results suggest a potential prognostic value for disease outcome evaluation.

Chorioamnionitis due to Lactococcus lactis cremoris: A case report.

Lactococcus lactis cremoris is rarely involved in human pathology. A thirty two-year old pregnant woman with premature rupture of membrane history presented with chorioamnionitis due to L. lactis cremoris. She underwent an emergency caesarian section and was treated with antibiotics including the association of amoxicillin and clavulanic acid. She was completely recovered. This is the first case to our knowledge of chorioamnionitis due to this organism.

[Parvovirus B19 seroprevalence in a group of schizophrenic patients]. / Séroprévalence du Parvovirus B19 dans un groupe de patients schizophrènes.

BACKGROUND: Schizophrenia is a highly disabling chronic mental illness. It is considerded as a neurodeveloppemental illness resulting from the interaction of genetic and environmental factors. Growing evidence supports the major role of prenatal infections and inflammation in the genesis of schizophrenia. The hypothesis including viral infections has been the subject of several studies and the role of parvovirus B19 (PB19) in the onset of the disease has been suggested. However, there is, up till now, no seroepidemiological evidence of his involvement. OBJECTIVE: To determine the prevalence of parvovirus B19 (PB19) in schizophrenic patients and in control subjects and to examine clinical associations between viral prevalence, risk factors of infectious disease and clinical features. METHOD: We carried out a case-control seroepidemiological study in the Psychiatry department of Farhat-Hached general hospital of Sousse (Tunisia). We recruited108 schizophrenic patients and 108 healthy controls free from any psychotic disorder and matched for age and sex. We collected sociodemographic data, medical history, axis I comorbid disorders and infectious risk factors. We assessed patients for psychopathology and severity of illness using respectively the Brief Psychiatric Rating Scale (BPRS), the Scale for the Assessment of Positive Symptoms (SAPS), the Scale for the Assessment of Negative Symptoms (SANS), the Positive and Negative Syndrome Scale (PANSS) and the Clinical Global Impressions (CGI). For each study participant, blood sample was collected and levels of IgG and IgM anti-PB19 were measured using the ELISA technique. RESULTS: The prevalence of IgG antibodies to PB19 was significantly higher in schizophrenic patients than in controls (73.1% vs 60.2%; P=0.04). There were no statistical differences between the two groups regarding the prevalence of IgM antibodies to PB19. No association was found between viral prevalence and sociodemographic data, risk factors for infection or clinical characteristics. The presence of PB19 antibodies was associated with a lower score on the PANSS negative subscale (P=0.04). No other signficative association were found. CONCLUSIONS: In our study, prevalence of IgG antibodies to PB19 was significantly higher in schizophrenic patients than in controls. This finding supports the hypothesis of the involvement of PB19 in schizophrenia. Further studies including both virological and immunological aspects are needed to better clarify the etiopathogenic mechanisms of schizophrenia which would challenge the management of this disease.

Identification of soluble and membrane antigenic markers of acquired toxoplasmosis by immunoblot.

The overall performance of quantitative assays in the detection of anti-Toxoplasma IgG is satisfactory, but discrepancies between assays are not uncommon especially when IgG concentrations are close to the limit of detection of the tests. The purpose of our study was to identify soluble and membrane antigens extracted from Toxoplasma gondii tachyzoites by immunoblot to select the most relevant antigenic bands to be used for qualitative serodiagnosis of acquired toxoplasmosis. We selected five relevant bands (98, 36, 33, 32 and 21 kDa) with soluble antigens and four relevant bands (42, 35, 32 and 30 kDa) with membrane antigens which gave high sensitivity and/or specificity in immunodiagnosis. The association on the same blot of at least three of the five relevant bands in the soluble antigen immunoblot showed the highest sensitivity/specificity (97.4%/99.0%, respectively). Our results indicate that immunoblot using soluble tachyzoite extract with simultaneous detection of at least three of the five bands (98, 36, 33, 32 and 21 kDa) represents a valuable test for serodiagnosis of acquired toxoplasmosis and should be further evaluated as a confirmatory test for sera which give discrepant results in quantitative assays.

Phenotype, genotype, and serotype distribution of macrolide resistant invasive and non-invasive Streptococcus pneumoniae strains, in Sousse, Tunisia.

OBJECTIVE: We determined the macrolide resistance phenotypes and genotypes in Streptococcus pneumoniae isolates in Sousse and assessed the serotype distribution. METHODS: We included S. pneumoniae strains isolated at our laboratory (2010-2013). The antimicrobial susceptibility was tested according to CA-SFM specifications. Serotyping was performed by agglutination of latex particles, to identify a subset of serotypes included in pneumococcal conjugate vaccines. The presence of macrolide resistance genes (ermB, mefA, mel) was detected by PCR. RESULTS: A total of 52.8% of 140 S. pneumoniae isolates were macrolide-resistant: MLSB (89.2%) and M (10.8%). The MLSB phenotypes were genotypically confirmed by ermB gene presence. 62% had decreased susceptibility to penicillin. The serotypes were: 14, 1, 23F, and 19A. Serotype coverage by PCV7, PCV10 and PCV13 was 44.2%, 73.6%, and 75.6% respectively. CONCLUSION: 50% of S. pneumoniae isolates were macrolide resistant. The MLSB phenotype encoded by the ermB gene was the most frequent. Serotype coverage seems inadequate.

Anti-C1q antibodies and systemic lupus erythematosus in the Tunisian population.

OBJECTIVES: The presence of a wide variety of autoantibodies is a characteristic feature of systemic lupus erythematosus (SLE). Although non-specific, anti-complement C1q (anti-C1q) were shown to correlate with the occurrence of active nephritis. The present study aimed to investigate the prevalence of anti-C1q in Tunisian SLE patients and their association with clinical manifestations, especially renal involvement. PATIENTS AND METHODS: IgG anti-C1q antibodies were assessed by Elisa in 98 SLE patients, 55 patients with rheumatoid arthritis (RA) and 65 healthy individuals (HI). RESULTS: Anti-C1q were found in 53 (54.1%) patients with SLE, three (5%) patients with RA and six (9.3%) HI. Among the 65 patients with renal involvement, anti-C1q were present in 35 (53.8%) patients. There was no significant association between anti-C1q and renal or extrarenal manifestations. In addition, there was no correlation between anti-C1q titer and SLEDAI index. Anti-C1q were significantly associated with anti-nucleosome (P=0.001), anti-Sm (P=0.01) and a low C4 level (P=0.046). Concomitant presence of anti-C1q and anti-dsDNA antibodies was not associated with renal manifestations. CONCLUSION: Our study shows that prevalence of anti-C1q was comparable with that previously reported in Caucasian populations. These antibodies were associated with a low C4 level. However, there was no association between anti-C1q and renal involvement or severity of nephritis.