Meta-analysis of hepatitis C seroconversion in relation to shared syringes and drug preparation equipment

Aims We conducted a systematic review of studies reporting seroincidence of hepatitis C infection (HCV) in relation to shared syringes and drug preparation equipment among injection drug users (IDUs). We identified published and unpublished studies that met inclusion criteria. Design We estimated the relative contributions of shared syringes and drug preparation equipment to HCV transmission using random‐effects meta‐analysis, and analyzed potential sources of heterogeneity of effects among studies. Findings Syringe sharing was associated with HCV seroconversion [pooled risk ratio (PRR) = 1.94, 95% confidence interval (CI) 1.53, 2.46], as was sharing drug preparation containers (PRR = 2.42, 95% CI 1.89, 3.10), filters (PRR = 2.61, 95% CI 1.91, 3.56), rinse water (PRR = 1.98, 95% CI 1.54, 2.56), combinations of this equipment (PRR = 2.24, 95% CI 1.28, 3.93) and ‘backloading’, a syringe‐mediated form of sharing prepared drugs (PRR = 1.86, 95% CI 1.41, 2.44). Meta‐regression results showed that the association between syringe sharing and seroconversion was modified by HCV seroprevalence in the IDU populations. Conclusions The risk of hepatitis C infection through shared syringes is dependent upon hepatitis C infection seroprevalence in the population. The risk of hepatitis C infection through shared drug preparation equipment is similar to that of shared syringes. Because the infection status of sharing partners is often unknown, it is important for injection drug users to consistently avoid sharing unsterile equipment used to prepare, divide or inject drugs and avoid backloading with an unsterile syringe.     

Surgical bacterial infections and antimicrobial susceptibility patterns at Lilongwe Central Hospital

A cross sectional study was done between October 1999 and February 2000 to determine antimicrobial susceptibility patterns of consecutive bacterial isolates of 102 clinical samples among surgical in-patients at Lilongwe Central Hospital (LCH), Malawi. Antimicrobial susceptibility was determined using comparative disc diffusion techniques. 83 (81.4%) samples were culture positive for bacterial growth while 19 (18.6%) grew nothing. Of the 93 culture positive specimens, Staphylococcus aureus was the predominant organism 43(51.8%) followed by Proteus species 8(9.6%) and E. coli 7(8.4%). Overall, 98.6% of all isolates tested against ciprofloxacin were susceptible, and against gentamicin and flucloxacin were 84.8% and 66.7% respectively. 59.3% of isolates tested against chloramphenicol were resistant. We recommend a review on the use of chloramphenicol as first-line antimicrobial therapy among surgical in-patients at Lilongwe Central Hospital. We also recommend restricted use of antimicrobials so as to minimise development of drug resistance. Periodic susceptibility studies are necessary to guide judicious use of antibiotics.     

The effects of GM-CSF and G-CSF in promoting growth of clonogenic cells in acute myeloblastic leukemia

A small subset of leukemic cells from most patients with acute myeloblastic leukemia (AML) have properties of stem cells and can be assayed by colony formation in agar or methylcellulose. Colony formation generally requires the addition of exogenous growth factors, but the exact factors required are incompletely defined. The AML colony- promoting activities of two recombinant human colony-stimulating factors (GM-CSF and G-CSF) were investigated by using blasts from 48 patients with AML. In nine cases, no colonies formed with either CSF. In seven cases colonies formed only in response to G-CSF and in 11 cases only in response to GM-CSF. In 21 cases colonies formed in response to either GM-CSF or G-CSF, and in 12 of these cases there was an additive effect between the two CSFs in determining maximum colony size. For cases responding to both GM- and G-CSF, the total number of colonies formed in response to the combination of both CSFs was almost always less than additive compared with the number of colonies formed in response to the individual CSFs. Further, the AML-CFU responding to either GM-CSF or G-CSF could not be distinguished by surface markers or by the cytochemical staining pattern of the colonies. These results suggest that there is considerable overlap between the GM-CSF- and G- CSF-responsive AML-CFU subpopulations in most cases. For five of seven cases, the combination of GM-CSF and G-CSF could replace a leukocyte feeder layer in providing maximum growth stimulation. These results indicate that GM-CSF and G-CSF are active growth factors for AML cells and are frequently additive in promoting maximum colony size.     

What's community got to do with it? Implementation models of syringe exchange programs.

Syringe exchange programs (SEPs) have been shown to be highly effective in reducing HIV transmission among injection drug users (IDUs). Despite this evidence, SEPs have not been implemented in many communities experiencing HIV epidemics among IDUs. We interviewed 17 key informants in nine U.S. cities to identify factors and conditions that facilitated or deterred the adoption of SEPs. Cities were selected to represent diversity in size, geographic location, AIDS incidence rates, and SEP implementation. Key informants included HIV prevention providers, political leaders, community activists, substance use and AIDS researchers, and health department directors. SEPs were established by one or more of three types of implementation models: (a) broad community coalition support, (b) community activist initiative, and (c) top-down decision making by government authorities. In each model, coalition building and community consultation were critical steps for the acceptance and sustainability of SEPs. When others were not prepared to act, community activists spearheaded SEP development, taking risks in the face of opposition, but often lacked the resources to sustain their efforts. Leadership from politicians and public health officials provided needed authority, clout, and access to resources. Researchers and scientific findings lent force and legitimacy to the effort. Rather than adopting adversarial positions, successful SEP implementers worked with or avoided the opposition. Fear of repercussions and lack of leadership were the greatest barriers to implementing SEPs. Communities that successfully implemented SEPs were those with activists willing to push the agenda, public officials willing to exercise leadership, researchers able to present authoritative findings, and proponents who effectively mobilized resources and worked to build community coalitions, using persistent but nonadversarial advocacy.