Prevalence of multidrug-resistant Gram-negative pathogens isolated from febrile neutropenic cancer patients with bloodstream infections in Egypt and new synergistic antibiotic combinations.

INTRODUCTION: Bloodstream infections with multidrug-resistant (MDR) Gram-negative bacteria (GNB) are among the most frequent complications in immunocompromised cancer patients because of their considerable morbidity and mortality. Several guidelines on antimicrobial therapy have addressed empirical treatment for such serious infections; however, the emergence of microbial resistance has become a significant problem worldwide. MATERIALS AND METHODS: In this study, starting from November 2015 to October 2016, a total of 529 blood specimens were collected from febrile neutropenic cancer patients at a tertiary care cancer hospital in Egypt. RESULTS: On examination for positive bacterial growth, it was found that 334 specimens showed no growth, while 195 were positive. Out of the 195 positive culture specimens, 102 (102/195, 52.3%) were Gram-negative and 93 (93/195, 47.7%) were Gram-positive. Out of the 102 GNB, 70 (70/102, 68.6%) were MDR, including Escherichia coli (27/70, 38.6%), Klebsiella pneumoniae (24/70, 34.3%), Acinetobacter baumannii (9/70, 12.8%), Enterobacter cloacae (4/70, 5.7%), Pseudomonas aeruginosa (2/70, 2.8%), Klebsiella oxytoca (2/70, 2.8%), and Klebsiella ornithinolytica (2/70, 2.8%). All MDR GNB showed high resistance to ampicillin, cefepime, ceftriaxone, and cephradine (minimum inhibitory concentration at which 50% of the isolates were inhibited [MIC50] >512 µg/mL for each). However, they showed good susceptibility to colistin (MIC50 <1 µg/mL). The most common extended-spectrum ß-lactamases (ESBLs) genes detected were ctx-m (39/70, 55.7%), shv (31/70, 44.3%), and tem (22/70, 31.4%). The most common aminoglycoside-resistant gene detected was aac(6')-Ib (42/70, 60%) followed by the plasmid-mediated quinolone resistance determinants; qnrA (2/70, 2.8%), qnrB (9/70, 12.8%), and qnrS (19/70, 27.1%). ESBL determinants were significantly associated with resistance to ciprofloxacin, levofloxacin, amikacin, and carbapenems (P-value <0.005). The fractional inhibitory concentration index for ampicillin/sulbactam plus ceftriaxone, ampicillin/sulbactam plus amikacin, and amikacin plus levofloxacin showed synergism against 29 (29/70, 41.4%), 19 (19/70, 27.1%), and 11 (11/70, 15.7%) isolates of the tested MDR GNB isolates, respectively. CONCLUSION: Accordingly, new empirical antibiotics should be administered including the use of colistin or meropenem alone or both against the MDR GNB in neutropenic cancer patients.

Dissemination of VIM-2 producing Pseudomonas aeruginosa ST233 at tertiary care hospitals in Egypt.

BACKGROUND: Pseudomonas aeruginosa is an important nosocomial pathogen, commonly causing infections in immunocompromised patients. The aim of this study was to examine the genetic relatedness of metallo-beta-lactamase (MBL) producing carbapenem resistant Pseudomonas aeruginosa clinical isolates collected from 2 tertiary hospitals in Cairo, Egypt using Multi Locus sequence typing (MLST). METHODS: Phenotypic and genotypic detection of metallo-beta-lactamase for forty eight non-duplicate carbapenem resistant P. aeruginosa isolates were carried out. DNA sequencing and MLST were done. RESULTS: The bla VIM-2 gene was highly prevalent (28/33 strains, 85%) among 33 MBL-positive P.aeruginosa isolates. MLST revealed eleven distinct Sequence Types (STs). A unique ST233 clone producing VIM-2 was documented by MLST in P.aeruginosa strains isolated from Cairo university hospitals. The high prevalence of VIM-2 producers was not due to the spread of a single clone. CONCLUSIONS: The findings of the present study clearly demonstrate that clones of VIM-2 positive in our hospitals are different from those reported from European studies. Prevalence of VIM-2 producers of the same clone was detected from surgical specimens whereas oncology related specimens were showing diverse clones.

The diagnostic value of C-reactive protein, interleukin-8, and monocyte chemotactic protein in risk stratification of febrile neutropenic children with hematologic malignancies.

BACKGROUND AND AIM: Recent advances in febrile neutropenia have highlighted the value of risk stratification especially that it can have important implications in terms of management. We aimed to identify a serum marker that may help to stratify febrile neutropenic pediatric patients treated for hematologic malignancies at the time of first evaluation. Thus, C-reactive protein (CRP), interleukin-8 (IL-8), and monocyte chemotactic protein-1-alpha (MCP-1-alpha) were evaluated for their predictive and diagnostic relevance in febrile episodes of cancer patients. PATIENTS AND METHODS: Within 24 hours of fever, CRP, IL-8, and MCP-1 serum levels were measured and the levels of these markers were related to the clinical findings of the patients. For this purpose, we collected and analyzed clinical data of 85 fever episodes occurring in 76 patients with hematologic malignancies, presenting to the Department of Pediatric Oncology, National Cancer Institute, Cairo University, during a 6-month period. RESULTS: Neutropenic children with febrile episodes were classified into 2 groups, a group with unexplainable fever (group I, n=26) and another group with either blood culture positive, and/or fever periods with a documented clinical sepsis and/or local infection (group II, n=59). Clinically, local sites of infection were encountered in 39 cases (45.9%), whereas a positive blood culture was detected in 20 cases. CRP, IL-8, and MCP-1 levels were significantly lower in group I versus group II (P value <0.001). There were overlaps of values between groups. CRP > or =90 mg/L was significantly associated with chemotherapy-related neutropenia and fever owing to bacteremia (P=0.038). The sensitivity, specificity, negative and positive predictive values of CRP, MCP-1, and IL-8 were (70%, 73%, 51%, and 85%), (64%, 92%, 53%, and 95%), and (71%, 77%, 54%, and 88%), respectively. Combining 2 or 3 markers improved the diagnostic performance of these test, as 78% of group II had elevated 2 or 3 markers versus 16% of the group with no evident infection. CONCLUSIONS: Low levels of CRP, MCP-1, and IL-8 could identify patients with unexplainable fever; whereas, high levels of these markers were of help in the diagnosis of infectious episodes. A model combining more than 1 marker is recommended in the assessment of febrile neutropenia.

Viral genomes and antigen detection of hepatitis B and C viruses in involved lymph nodes of Egyptian non-Hodgkin's lymphoma patients.

Several studies have suggested an association between Hepatitis C and B viruses (HCV and HBV) and non-Hodgkin's lymphoma (NHL). In the present study we have searched for viral genomes and antigens in the malignant lymphoma tissues as well as their seroprevalence. Antibodies against Hepatitis C as well as HCV RNA and hepatitis B surface antigen (HBsAg) were determined for 29 newly diagnosed non-Hodgkin's lymphoma patients using an enzyme linked immunosorbent assay (ELISA), as well as RT-PCR and compared with 36 apparently healthy individuals as a control group for viral markers. Immunohistochemical staining (IHC) was performed on paraffin embedded tissues for the NS3 of HCV and for HBsAg of HBV using the immunoperoxidase technique. Paraffin embedded lymph nodes (LN) were studied for the presence of viral sequences. Ten non-metastatic lymph nodes (LN) from cancer cases other than NHL were used as a control for IHC and molecular studies. HCV was significantly more encountered in patients with NHL when compared to controls for both antibodies (27.6% versus 8.3% of serum controls; p = 0.04), and antigens studied by IHC in the involved LN (41% versus 10% of tissue controls; p = 0.06). Although HBsAg positivity was not different in NHL patients when compared to controls (6.9% and 2.7%); yet it was significantly more encountered in LN of NHL patients (p = 0.04). HBV-DNA was detected in 27.5% of patient's samples and none of the controls. In conclusion, overall our findings confirm the presence of HBV and HCV antigens and viral sequences in the involved LNs of NHL patients, except for HCV RNA which perhaps necessitates fresh and not paraffin embedded tissues. These results strengthen the assumption that these viruses may be involved in the development of NHL.

HLA alleles in Egyptian HCV genotype-4 carriers.

Risk factors affecting asymptomatic HCV carriers as well as intrafamilial HCV transmission are not completely known. We hypothesized that immunological factors related to HLA profiles may affect the intrafamilial transmission. We investigated the possible association between HLA class I & II genes and the presence of HCV infection, as well as their possible role in intrafamilial tramsmition. One hundred forty five individuals comprising 40 families were recruited from bone marrow transplantation (BMT) unit at the National Cancer Institute, Cairo University. Serologic class I and generic class II MHC alleles were determined. Hepatitis C virus was detected by enzyme immunoassay (EIA) and confirmed by INNO-LIA. Detection of viral RNA was also confirmed by RT-PCR and HCV genotyping was done by immunoblotting (INNO-LiPA) and direct sequencing by TrueGene kit. Out of the 145 serum samples, 33 were positive for HCV antibodies by EIA and confirmed by both immunoblotting techniques and RT-PCR. Twenty-eight of them were eligible for HCV typing. The genotypes detected were 4, 2a, 1a and 1b. A mixed infection by more than one genotype was detected in 9 cases. Six families had 2 or more members reactive for HCV antibodies. Intrafamilial transmission was confirmed by HCV-sequence in 3 families. HLA class I & II alleles A28, A29, B14 & DR7 were significantly encountered in HCV positive than negative cases (p=0.040, 0.003, 0.001 & 0.010 respectively). In addition, two cases showed evidence of viral clearance, both expressed B50 (21) allele. We conclude that, there is a possible impact of both class I and class II alleles on HCV infection, resistance, clearance and intrafamilial transmission.

Parvovirus B19 infection as a cause of anemia in pediatric acute lymphoblastic leukemia patients during maintenance chemotherapy.

PURPOSE: Persistent parvovirus B19 tends to occur in immunocom-promised patients and manifests as pure red cell aplasia and chronic anemia. This study aimed to detect the contribution of parvovirus B19 infection to anemia in children with acute lymphoblastic leukemia (ALL) receiving chemotherapy. PATIENTS AND METHODS: Two groups of ALL patients were studied during maintenance chemotherapy: 50 patients with persistent anemia (ie, extending for >2 weeks) and 34 patients without anemia (controls). Serum parvovirus B19 IgG and IgM were investigated by an enzyme-linked immunosorbent assay, and the virus DNA was sought in bone marrow cells by a nested polymerase chain reaction assay. RESULTS: Parvovirus B19 DNA was detected in 11 of the 50 (22%) ALL children with anemia, 4 of whom were also IgM positive. In addition, IgM positivity was observed in nine (18%) other children who were negative for parvovirus B19 DNA. The children without anemia were found to be significantly different than those with anemia in terms of parvovirus B19 DNA positivity and DNA + IgM positivity (P = 0.03 and 0.01, respectively). IgG was found to be positive in a total of 19 (38%) cases, with B19 DNA present in 6 of them. CONCLUSIONS: These findings indicate the high frequency of parvovirus B19 in anemia in children with ALL and the importance of testing for its DNA in the bone marrow cells together with IgG and IgM antibodies in the serum of immunocompromised patients. It is important to consider parvovirus B19 infections as a cause of anemia and suppressed erythropoiesis in children with ALL who are receiving ongoing treatment.

Hepatitis C virus and its genotypes and Helicobacter pylori in pediatric non-Hodgkin's lymphoma: could there be a possible etiologic role?

BACKGROUND: It has been recently hypothe-sized that Helicobacter pylori (H. pylori) and Hepatitis C virus (HCV) might be involved in the pathogenesis of malignant non-Hodgkin's lymphoma (NHL). However, most of the studies were carried out on adult patients. On the basis of this observation, we sought to determine the prevalence of these infections in pediatric NHL patients at National Cancer Institute (NCI) and whether there is any clinical or histopathologic picture linked to the presence of these infectious agents. PATIENTS AND METHODS: The study was performed on 119 pediatric NHL patients, either as new or relapse cases, at the hematology out patient clinic of NCI from January 2002 to July 2003. Thirty apparently healthy children were studied as the control. We searched for H. pylori IgG antibodies using an enzyme immuno-assay (EIA) procedure. HCV was investigated by EIA to detect its antibodies, reverse transcriptase polymerase chain reaction (RT-PCR) for the presence of its RNA and viral sequencing for the determination of the viral genotype. RESULTS: Antibodies for H. pylori were detected in 51/119 (43.2%) and in none of the control group, p