Case report of Curtobacterium isolated from a catheter tip sample misidentified as Cronobacter.

The Curtobacterium genus is a member of the family Microbacteriaceae, and Curtobacterium species are recognized as plant pathogens. The aim of this study was to investigate a dubious result of species identification for an infection located on a catheter tip of a patient with Covid-19. A strain isolated from a catheter tip sample, identified by VITEK® 2 as Cronobacter spp., was submitted to polyphasic analysis: Matrix-Assisted Laser Desorption Ionization-Time of Flight Mass Spectrometry (MALDI-TOF MS) using VITEK® MS, real-time polymerase chain reaction targeting dnaG gene, and 16S rRNA full gene Sanger sequencing analysis for confirmation. The strain presented negative result using qPCR and could not identified by MALDI-TOF MS. 16S rRNA full gene Sanger sequencing analysis identified the strain as Curtobacterium spp. The Gram-variable characteristic (Gram-negative instead of Gram-positive) of the isolated strain was the responsible for the misidentification by VITEK® 2 and VITEK® MS did not identify the strain. 16S rRNA full gene sequencing analysis identified the strain as Curtobacterium genus, but other complementary techniques are necessary to identify at species level.

Cytotoxicity profile of Cronobacter species isolated from food and clinical specimens in Brazil.

AIMS: The objective of this study was to evaluate the cytotoxic activity of Cronobacter strains isolated from foods (n = 50) and clinical samples (n = 6) in Brazil and genotype selected strains (n = 18) using multi-locus sequence typing (MLST) METHODS AND RESULTS: The cytotoxic activity of C. sakazakii (n = 29), C. dublinensis (n = 13), C. malonaticus (n = 6), C. turicensis (n = 6) and C. muytjensii (n = 2) was screened using Vero, RK13, Hep2c, NCTC clone 929 and BHK-21 cell lines. Selected Cronobacter strains were assigned to C. sakazakii ST 21, C. turicensis ST 252, C. sakazakii ST 647, and three newly assigned STs: C. turicensis STs 738-740. The maximum death caused by non-heat-treated filtrates was 20·4, 86·2, 47·0 and 84·0%, in Vero, RK13, Hep2c and NCTC clone 929 cells, respectively. These were caused by C. sakazakii strains C291 and C292 (ST 494) which had been isolated during neonatal Cronobacter meningitis infection, and C110 (ST 395) isolated from flaxseed flour. Thermal treatment (100°C/20 min) significantly reduced the cytotoxicity activity in NCTC clone 929 and Vero cells (P ≤ 2 × 10-6 ), but not in RK13 (P = 0·12) and Hep2c (P = 0·85), indicating the cytotoxin(s) were probably proteinaceous. Electron microscopy revealed that cytotoxic compounds from C. sakazakii induced several cell death characteristics, including loss of cell-cell contact, microvilli reduction and cellular lysis. Autophagic vacuoles and mitochondrial damage were the most common ultrastructural features observed. CONCLUSIONS: It was concluded that Cronobacter strains, especially C. sakazakii, could produce heat-labile cytotoxic compounds in cell filtrates. SIGNIFICANCE AND IMPACT OF THE STUDY: This study providing insights into the pathogenesis of the Cronobacter genus. Cytotoxins were identified in excreted filtrates of C. sakazakii strains isolated from food and clinical specimens. The presence of Cronobacter strains that can produce cytotoxins in foods can be a potential threat to human health and highlight the need for high levels of hygiene.

Occurrence of total coliforms, Escherichia coli and Cronobacter species in commercially available 20 l bottled drinking water sold in Rio de Janeiro State, Brazil.

Cronobacter infections of infants are commonly regarded as due to the ingestion of contaminated feed. The aim of this study was to determine the occurrence of Cronobacter, total coliforms and Escherichia coli in different brands of natural mineral waters as sold in 20 l returnable bottles in Rio de Janeiro, Brazil. The quantification of total coliforms and E. coli was performed by Most Probable Number. The detection of Cronobacter was as according to the ISO 22964:2017 and Bacteriological Analytical Manual/FDA. Molecular characterization of Cronobacter isolates was performed by real-time PCR and by multi-locus sequence typing. The antibiotic susceptibility profile was determined and biofilm production was evaluated in polystyrene microplates. Total coliforms and E. coli were detected in 13 (39·4%) and 2 (6·1%) of the 33 lots analysed respectively, and were considered unsatisfactory for human consumption according to Brazilian law. One (3·0%) lot showed contamination by C. malonaticus ST440 (Cronobacter MLST Databases accession no. ID 2646). The strain was susceptible to all (n = 13) antibiotics tested and only formed a weak biofilm. Since there is a high consumption of natural mineral waters by elderly and immunosuppressed persons, epidemiological surveillance agencies should be aware of the risk that these waters may represent for these groups. SIGNIFICANCE AND IMPACT OF THE STUDY: Cronobacter malonaticus ST440 was isolated from 20 l bottled drinking natural mineral waters sold in markets in Rio de Janeiro State, Brazil, and can be a potential threat to human health, particularly for neonates. Thirteen lots (39·4%) were unsatisfactory for human consumption due to the presence of total coliforms and/or Escherichia coli.

DNA sequence-based re-assessment of archived Cronobacter sakazakii strains isolated from dairy products imported into China between 2005 and 2006.

BACKGROUND: Cronobacter species are associated with severe foodborne infections in neonates and infants, with particular pathovars associated with specific clinical presentations. However, before 2008 the genus was regarded as a single species named Enterobacter sakazakii which was subdivided into 8 phenotypes. This study re-analyzed, using multi-locus sequence typing (MLST) and whole genome sequence with single nucleotide polymorphism analysis (WGS-SNP), 52 strains which had been identified as Enterobacter sakazakii as according to the convention at the time of isolation. These strains had been isolated from dairy product imports into China from 9 countries between 2005 and 6. Bioinformatic analysis was then used to analyze the relatedness and global dissemination of these strains. RESULT: FusA allele sequencing revealed that 49/52 strains were Cronobacter sakazakii, while the remaining 3 strains were Escherichia coli, Enterobacter cloacae, and Franconibacter helveticus. The C. sakazakii strains comprised of 8 sequence types (STs) which included the neonatal pathovars ST1, ST4 and ST12. The predominant sequence type was ST13 (65.3%, 32/49) which had been isolated from dairy products imported from 6 countries. WGS-SNP analysis of the 32 C. sakazakii ST13 strains revealed 5 clusters and 5 unique strains which did not correlate with the country of product origin. CONCLUSION: The mis-identification of E. coli, E. cloacae and F. helveticus as Cronobacter spp. reinforces the need to apply reliable methods to reduce the incidence of false positive and false negative results which may be of clinical significance. The WGS-SNP analysis demonstrated that indistinguishable Cronobacter strains within a sequence type can be unrelated, and may originate from multiple sources. The use of WGS-SNP analysis to distinguishing of strains within a sequence type has important relevance for tracing the source of outbreaks due to Cronobacter spp.

Survival of Cronobacter in powdered infant formula and their variation in biofilm formation.

Cronobacter is a ubiquitous Gram-negative pathogen bacterium capable of surviving in low water activity environments, in particular powdered infant formula (PIF). Seven Cronobacter strains representing four different species (C. sakazakii, n = 4; C. malonaticus, n = 1; C. muytjensii, n = 1; C. turicensis, n = 1) were subjected to dry stress and stored in PIF at room temperature. The resulting survivor curves showed that Cronobacter sp. can survive for extended periods of at least 3 months with a significant, but moderate, variability regarding the level of resistance between species; however, no correlation was evident regarding the origin of strains. These results are evaluated with regard to other key characteristics, including genomic profiles and biofilm formation capacities of the strains. SIGNIFICANCE AND IMPACT OF THE STUDY: Cronobacter can survive extended periods of at least 3 months in PIF, with moderately significant interspecific variability in desiccation resistance. Results are evaluated with regard to genomic profiles and biofilm formation capacities of the strains, and contribute to an improved understanding of the environmental persistence of Cronobacter in contaminated PIF, and subsequent risk to infant exposure.

Reducing exposure to pathogens in the horse: a preliminary study into the survival of bacteria on a range of equine bedding types.

AIMS: To compare the rate of growth of four microbial strains that cause disease in the horse, on four commonly used types of bedding. The moisture-holding capacity of each bedding type was also tested. METHODS AND RESULTS: Microbial strains included Streptococcus equi, Streptococcus zooepidemicus, Fusobacterium necrophorum, Dichelobacter nodosus and Dermatophilus congolensis. The bedding types tested were Pinus sylvestris (Scots pine shavings), Pinus nigra (Corsican pine shavings), Picea sitchensis (Sitka spruce shavings), Cannabis sativa (hemp) and chopped wheat straw. A suspension of each microbial strain was spread in triplicate on agar media and incubated in its optimal growth conditions. The viable count (colony-forming unit per ml) was determined for each bacterial strain for the five different bedding types. Pinus sylvestris bedding resulted in significantly less (P = 0·001) bacterial growth of all strains tested. CONCLUSIONS: Factors resulting in the inhibition of bacterial growth include the antibacterial effects reported in the Pinacea family and the physical properties of the bedding substrate. Research is currently focussed on the diagnosis and management of disease. Prevention of disease is also important for matters of biosecurity. Strategies should include the provision of a hygienic environment and the use of specific types of bedding. SIGNIFICANCE AND IMPACT OF THE STUDY: Bedding choice has implications for global equine health and disease prevention as well as potential benefits in other animal species.

Capsular profiling of the Cronobacter genus and the association of specific Cronobacter sakazakii and C. malonaticus capsule types with neonatal meningitis and necrotizing enterocolitis.

BACKGROUND: Cronobacter sakazakii and C. malonaticus can cause serious diseases especially in infants where they are associated with rare but fatal neonatal infections such as meningitis and necrotising enterocolitis. METHODS: This study used 104 whole genome sequenced strains, covering all seven species in the genus, to analyse capsule associated clusters of genes involved in the biosynthesis of the O-antigen, colanic acid, bacterial cellulose, enterobacterial common antigen (ECA), and a previously uncharacterised K-antigen. RESULTS: Phylogeny of the gnd and galF genes flanking the O-antigen region enabled the defining of 38 subgroups which are potential serotypes. Two variants of the colanic acid synthesis gene cluster (CA1 and CA2) were found which differed with the absence of galE in CA2. Cellulose (bcs genes) were present in all species, but were absent in C. sakazakii sequence type (ST) 13 and clonal complex (CC) 100 strains. The ECA locus was found in all strains. The K-antigen capsular polysaccharide Region 1 (kpsEDCS) and Region 3 (kpsMT) genes were found in all Cronobacter strains. The highly variable Region 2 genes were assigned to 2 homology groups (K1 and K2). C. sakazakii and C. malonaticus isolates with capsular type [K2:CA2:Cell(+)] were associated with neonatal meningitis and necrotizing enterocolitis. Other capsular types were less associated with clinical infections. CONCLUSION: This study proposes a new capsular typing scheme which identifies a possible important virulence trait associated with severe neonatal infections. The various capsular polysaccharide structures warrant further investigation as they could be relevant to macrophage survival, desiccation resistance, environmental survival, and biofilm formation in the hospital environment, including neonatal enteral feeding tubes.

The speciation and genotyping of Cronobacter isolates from hospitalised patients.

The World Health Organization (WHO) has recognised all Cronobacter species as human pathogens. Among premature neonates and immunocompromised infants, these infections can be life-threatening, with clinical presentations of septicaemia, meningitis and necrotising enterocolitis. The neurological sequelae can be permanent and the mortality rate as high as 40-80%. Despite the highlighted issues of neonatal infections, the majority of Cronobacter infections are in the elderly population suffering from serious underlying disease or malignancy and include wound and urinary tract infections, osteomyelitis, bacteraemia and septicaemia. However, no age profiling studies have speciated or genotyped the Cronobacter isolates. A clinical collection of 51 Cronobacter strains from two hospitals were speciated and genotyped using 7-loci multilocus sequence typing (MLST), rpoB gene sequence analysis, O-antigen typing and pulsed-field gel electrophoresis (PFGE). The isolates were predominated by C. sakazakii sequence type 4 (63%, 32/51) and C. malonaticus sequence type 7 (33%, 17/51). These had been isolated from throat and sputum samples of all age groups, as well as recal and faecal swabs. There was no apparent relatedness between the age of the patient and the Cronobacter species isolated. Despite the high clonality of Cronobacter, PFGE profiles differentiated strains across the sequence types into 15 pulsotypes. There was almost complete agreement between O-antigen typing and rpoB gene sequence analysis and MLST profiling. This study shows the value of applying MLST to bacterial population studies with strains from two patient cohorts, combined with PFGE for further discrimination of strains.

Effect of heat shock and recovery temperature on variability of single cell lag time of Cronobacter turicensis.

The effect of heat stress and subsequent recovery temperature on the individual cellular lag of Cronobacter turicensis was analysed using optical density measurements. Low numbers of cells were obtained through serial dilution and the time to reach an optical density of 0.035 was determined. Assuming the lag of a single cell follows a shifted Gamma distribution with a fixed shape parameter, the effect of recovery temperature on the individual lag of untreated and sublethally heat treated cells of Cr. turicensis were modelled. It was found that the shift parameter (Tshift) increased asymptotically as the temperature decreased while the logarithm of the scale parameter (θ) decreased linearly with recovery temperature. To test the validity of the model in food, growth of low numbers of untreated and heat treated Cr. turicensis in artificially contaminated infant first milk was measured experimentally and compared with predictions obtained by Monte Carlo simulations. Although the model for untreated cells slightly underestimated the actual growth in first milk at low temperatures, the model for heat treated cells was in agreement with the data derived from the challenge tests and provides a basis for reliable quantitative microbiological risk assessments for Cronobacter spp. in infant milk.

Realizing the potential for HIV self-testing.

HIV self-testing (HIVST), a process in which an individual performs a HIV rapid diagnostic test and interprets the result in private, is an emerging approach that is well accepted, potentially cost-effective and empowering for those who may not otherwise test. To further explore the potential of HIVST, the Liverpool School of Tropical Medicine and World Health Organization held the first global symposium on the legal, ethical, gender, human rights and public health implications of HIVST. The meeting highlighted the potential of HIVST to increase access to and uptake of HIV testing, and emphasized the need to further develop evidence around the quality of HIVST and linkage to post-test services, and to assess the risks and the benefits associated with scale-up. This special issue of AIDS and Behavior links directly to the symposium and presents some of the latest research and thinking on the scale-up of HIV self-testing.

Genotypic and phenotypic characteristics of Cronobacter species, with particular attention to the newly reclassified species Cronobacter helveticus, Cronobacter pulveris, and Cronobacter zurichensis.

In 2013, Enterobacter helveticus, Enterobacter pulveris and Enterobacter turicensis, were reclassified as Cronobacter helveticus, Cronobacter pulveris and Cronobacter zurichensis, respectively. Previously these species had been used as negative controls for some Cronobacter detection assays. This study examined cultural, biochemical and molecular Cronobacter detection and identification assays, with emphasis on the new species. Additionally, 32 Cronobacter genomes were examined for the presence of PCR target genes using the BLAST function of the online Cronobacter PubMLST facility. The results of the cultural methods varied and no single medium was able to correctly detect all Cronobacter spp. Since the supporting databases have not been updated to include the Cronobacter genus, Enterobacter sakazakii was returned for four strains of the newly reclassified species with ID32E and none with API 20E. PCR probes targeting rpoB and ompA could not correctly identify the new Cronobacter spp., due to primer specificity or absent target genes. As neonates have been identified as a high-risk group for infection, international standards require the absence of all Cronobacter species in powdered infant formula. However, many conventional detection methods cannot correctly identify the newly recognized species. Conversely, DNA sequence-based methods can adapt to taxonomic revisions and will likely become more common.

Epidemiology of Cronobacter spp. isolates from patients admitted to the Olomouc University Hospital (Czech Republic).

UNLABELLED: The data on the incidence of Cronobacter spp. was collated from hospital records for the seven-year period 2005-2011. The majority of Cronobacter spp. isolates (n = 91) were from throat swabs (61), followed by urine (5), tracheal aspirates (5), bronchoalveolar lavage (4), cannulae (4), and sputum (3) samples. This is the first study which profiles the carriage of Cronobacter spp. according to patient age, based on seven years of clinical data from 2005-2011. It reveals a high recovery (63.7% of strains, n = 91) of the organism from children, 1-14 years in age. KEYWORDS: Cronobacter spp. - meningitis - nosocomial infection.

Microbiological assessment and evaluation of rehydration instructions on powdered infant formulas, follow-up formulas, and infant foods in Malaysia.

A total of 90 samples comprising powdered infant formulas (n=51), follow-up formulas (n=21), and infant foods (n=18) from 15 domestic and imported brands were purchased from various retailers in Klang Valley, Malaysia and evaluated in terms of microbiological quality and the similarity of rehydration instructions on the product label to guidelines set by the World Health Organization. Microbiological analysis included the determination of aerobic plate count (APC) and the presence of Enterobacteriaceae and Cronobacter spp. Isolates of interest were identified using ID 32E (bioMérieux France, Craponne, France). In this study, 87% of powdered infant formulas, follow-up formulas, and infant foods analyzed had an APC below the permitted level of <10(4) cfu/g. These acceptable APC ranged between <10(2) to 7.2×10(3) cfu/g. The most frequently isolated Enterobacteriaceae was Enterobacter cloacae, which was present in 3 infant formulas and 1 infant food tested. Other Enterobacteriaceae detected from powdered infant and follow-up formulas were Citrobacter spp., Klebsiella spp., and other Enterobacter spp. No Cronobacter species were found in any samples. Rehydration instructions from the product labels were collated and it was observed that none directed the use of water with a temperature >70°C for formula preparation, as specified by the 2008 revised World Health Organization guidelines. Six brands instructed the use of water at 40 to 55°C, a temperature range that would support the survival and even growth of Enterobacteriaceae.

Diversity of the Cronobacter genus as revealed by multilocus sequence typing.

Cronobacter (previously known as Enterobacter sakazakii) is a diverse bacterial genus consisting of seven species: C. sakazakii, C. malonaticus, C. turicensis, C. universalis, C. muytjensii, C. dublinensis, and C. condimenti. In this study, we have used a multilocus sequence typing (MLST) approach employing the alleles of 7 genes (atpD, fusA, glnS, gltB, gyrB, infB, and ppsA; total length, 3,036 bp) to investigate the phylogenetic relationship of 325 Cronobacter species isolates. Strains were chosen on the basis of their species, geographic and temporal distribution, source, and clinical outcome. The earliest strain was isolated from milk powder in 1950, and the earliest clinical strain was isolated in 1953. The existence of seven species was supported by MLST. Intraspecific variation ranged from low diversity in C. sakazakii to extensive diversity within some species, such as C. muytjensii and C. dublinensis, including evidence of gene conversion between species. The predominant species from clinical sources was found to be C. sakazakii. C. sakazakii sequence type 4 (ST4) was the predominant sequence type of cerebral spinal fluid isolates from cases of meningitis.

Survival and growth of Cronobacter species (Enterobacter sakazakii) in wheat-based infant follow-on formulas.

AIMS: To determine the survival and growth characteristics of Cronobacter species (Enterobacter sakazakii) in infant wheat-based formulas reconstituted with water, milk, grape juice or apple juice during storage. METHODS AND RESULTS: Infant wheat-based formulas were reconstituted with water, ultra high temperature milk, pasteurized grape or apple juices. The reconstituted formulas were inoculated with Cronobacter sakazakii and Cronobacter muytjensii and stored at 4, 25 or 37 degrees C for up to 24 h. At 25 and 37 degrees C, Cronobacter grew more (>5 log(10)) in formulas reconstituted with water or milk than those prepared with grape or apple juices (c. 2-3 log(10)). The organism persisted, but did not grow in any formulas stored at 4 degrees C. Formulas reconstituted with water and milk decreased from pH 6.0 to 4.8-5.0 after 24 h, whereas the pH of the formulas reconstituted with fruit juices remained at their initial pH values, c. pH 4.8-5.0. CONCLUSIONS: Cronobacter sakazakii and C. muytjensii can grow in reconstituted wheat-based formulas. If not immediately consumed, these formulas should be stored at refrigeration temperatures to reduce the risk of infant infection. SIGNIFICANCE AND IMPACT OF THE STUDY: The results of this study will be of use to regulatory agencies and infant formula producers to recommend storage conditions that reduce the growth of Cronobacter in infant wheat-based formulas.

Estimating the cost of diagnosing HIV at birth in Lesotho.

BACKGROUND: Infants with HIV infection, particularly those infected in utero, who do not receive antiretroviral therapy (ART) have high mortality in the first year of life. Virologic diagnostic testing is recommended by the World Health Organization between ages 4 and 6 weeks after birth. However, adding very early infant diagnosis (VEID) testing at birth has been suggested to enable earlier diagnosis and rapid treatment of in utero infection. We assessed the costs of adding VEID to the standard 6-week testing in Lesotho where coverage of PMTCT services is nearly universal. METHODS: Retrospective cost data were collected at eight health-care facilities in three districts participating in an observational prospective study that included birth testing as well as at the National Reference Laboratory in Lesotho, to investigate the cost-per-infection identified. Extrapolating to the national level, it was possible to estimate the impact of VEID on the identification of HIV-infected infants. RESULTS: The unit cost-per-VEID test in Lesotho in 2015 was $40.50. Major cost drivers were supplies/commodities (46%) and clinical labor (22%). In 2015, 66.3% of cohort study infants born at study facilities underwent VEID; one out of 199 infants had a positive HIV DNA PCR test at birth (0.5% potential in utero infection), yielding a cost of $8,060 per HIV-positive infant identified. Sensitivity analysis showed costs based on Lesotho costing data ranged from $810 to $16,194 per-infected child with varying in utero infection rates from 5% and 0.25%, respectively. With 11,157 HIV-exposed births nationally from pregnant women on PMTCT, 66.3% VEID coverage, and 0.5% in utero infection, 37 infants infected with HIV could have been identified at birth in 2015 and 8 early infant deaths potentially averted with immediate ART compared with waiting for 6-week testing. CONCLUSION: If Lesotho costing data from this pilot study were applied to different epidemic circumstances, the cost-per-infected child identified by adding VEID birth testing to standard 6-week testing was lowest when in utero infection rates were high (when HIV prevalence is high and PMTCT coverage is low).

Behaviour change in clients of health centre-based voluntary HIV counselling and testing services in Kenya.

OBJECTIVE: To explore behaviour change, baseline risk behaviour, perception of risk, HIV disclosure and life events in health centre-based voluntary counselling and testing (VCT) clients. DESIGN AND SETTING: Single-arm prospective cohort with before-after design at three (one urban and two rural) government health centres in Kenya; study duration 2 years, 1999-2001. SUBJECTS: Consecutive eligible adult clients. MAIN OUTCOME MEASURES: Numbers of sexual partners, partner type, condom use, reported symptoms of sexually transmitted infection, HIV disclosure and life events. RESULTS: High rates of enrollment and follow-up provided a demographically representative sample of 401 clients with mean time to follow-up of 7.5 months. Baseline indicators showed that clients were at higher risk than the general population, but reported a poor perception of risk. Clients with multiple partners showed a significant reduction of sexual partners at follow-up (16% to 6%; p<0.001), and numbers reporting symptoms of sexually transmitted infection decreased significantly also (from 40% to 15%; p<0.001). Condom use improved from a low baseline. Low rates of disclosure (55%) were reported by HIV-positive clients. Overall, no changes in rates of life events were seen. CONCLUSION: This study suggests that significant prevention gains can be recorded in clients receiving health centre-based VCT services in Africa. Prevention issues should be considered when refining counselling and testing policies for expanding treatment programmes.

Retrospective utility of bronchoscopy after hematopoietic stem cell transplant.

Fiberoptic bronchoscopy with bronchoalveolar lavage (BAL) is thought to be the procedure of choice to evaluate pulmonary infiltrates in hematopoietic stem cell transplant (HSCT) recipients. We retrospectively reviewed 91 bronchoscopies performed on 190 in-patient HSCT recipients admitted or treated for pneumonia from January 1994 to December 2004. These yielded a diagnosis 49% of the time with an overall survival of 35 days post-bronchoscopy. We were unable to detect any survival benefit from an addition to the treatment regimen after a positive result from analysis of the BAL fluid or transbronchial biopsy. The most common bacteria isolated was Pseudomonas that was often resistant to the patient's current antibiotics, suggesting that in lieu of this diagnostic procedure, changes to better cover resistant Gram-negative bacteria are reasonable. Although transbronchial biopsies provided an additional diagnosis in one out of 21 biopsies performed, six of the seven complications in our series were directly related to the transbronchial biopsy. With approximately a 50% yield from a bronchoscopy, additional treatment given after only 20% of all bronchoscopies, and no detectable survival benefit with a bronchoscopy that yielded a diagnosis, the utility of a bronchoscopy in this patient population is questioned by these data.

Hippocampal pyramidal cell disarray in schizophrenia as a bilateral phenomenon.

In a continuing quantitative study of hippocampal cell orientation in schizophrenic subjects and nonschizophrenic control subjects, a pattern of right hemispheric cell disorganization in schizophrenic subjects, as robust as that previously described in the left hemisphere, was shown. The study was based on tissue from 11 schizophrenic and seven approximately age-matched control subjects from a Veterans Administration Medical Center. Using a new measuring technique that proved complementary and superior to the method formerly used, we determined the axes of orientation for approximately 10,800 neurons. A significant difference in cell disorganization was found between schizophrenic and control subjects. From separate analyses of the interface zones among the various hippocampal cell sectors, this difference was found to be significant at the interfaces between cornu ammonis zones 1 and 2 and zones 2 and 3. Analysis of the pattern of disorganization numbers suggests a bimodal distribution in which the cell orientation values of one group of schizophrenic subjects overlap those of the nonschizophrenic control group, while the cell orientation values of a second group significantly exceed those of the control population. Although some recent studies have suggested that schizophrenia may be related exclusively to the left hemisphere, the results of this study indicate that schizophrenia-related structural changes involve the right hemisphere as well. Thus, schizophrenia may be a bilateral rather than unilateral disorder.

The affordability of antiretroviral therapy in developing countries: what policymakers need to know.

OBJECTIVE: The objective of this paper is to assist policymakers in developing countries and international donors by providing an outline of economic information needed to make a decision regarding the purchase of drugs to provide highly active antiretroviral therapy (HAART). DESIGN: The following paper: (i) reviews existing experiences of policymakers in developing countries regarding the purchase of drugs needed for HAART, (ii) identifies issues that would need to be addressed and data that would be required to make more informed decisions regarding this issue, (iii) develops a cost-benefit model that could be utilized in designing an economic research project evaluating the economic costs and benefits of HAART, and (iv) performs a preliminary test of this model with data from Costa Rica. RESULTS: A review of experiences with this issue reveals that there are growing political, legal and budgetary pressures for countries to make tenable decisions regarding the purchase of drugs for HAART. An economic model describing the costs and benefits of HAART is proposed, although much of the required data for using such a model is currently neither available or in the process of being collected. CONCLUSIONS: It is imperative that economic data be collected to better inform policymakers in developing countries about their decision regarding the purchase of these drugs. It is recommended that such economic data be collected as organizations such as the United Nations Joint Programme on HIV/ AIDS (UNAIDS) initiate their medical assessments of HAART in developing countries.

PIP: The ideal treatment strategy for people with AIDS (PWAs), involving the use of one or more protease inhibitors and 2 reverse transcriptase inhibitors, is known as highly active antiretroviral therapy (HAART). HAART is greatly helping PWAs, sometimes enabling patients in the final stages of AIDS to regain enough health and strength to again actively and productively participate in society. With such successes in developed countries, policymakers in developing countries are increasingly being pressured to provide HAART for their own populations. The drugs needed for HAART, however, are very expensive and may require administration throughout the remainder of the life of the PWA. Few, if any, similarly expensive drugs are currently available in developing countries. The author reviews existing experiences of policymakers in developing countries on the purchase of drugs needed for HAART, identifies the issues to address and data needed to make more informed decisions on the subject, develops a cost-benefit model which could be used to design an economic research project evaluating the economic costs and benefits of HAART, and tests the model with data from Costa Rica. Political, legal, and budgetary pressures are mounting for countries to make viable decisions on buying drugs for HAART. An economic model describing the costs and benefits of HAART is proposed, although much of the required data for using such a model is currently neither available nor being collected.