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Campylobacter jejuni-related diarrheal diseases is one of the major health issues among young children (0-59 months old) in low-income countries. Monitoring of the capsular (capsule polysaccharide, CPS) types of virulent C. jejuni strains in regions where the disease is endemic is of great importance for the development of a customized capsule-based multivalent vaccine. Therefore, we aimed to determine the prevalence of CPS genotypes among C. jejuni strains isolated from young children with enteritis (n = 152) and asymptomatic carriers matched by age, sex, and residence defined as the control group (n = 215) in Bangladesh. CPS genotyping was performed using a newly established multiplex polymerase chain reaction (PCR) method and lipooligosaccharide (LOS) locus classes (A-E) were characterized using PCR as well. We identified 24 different CPS genotypes among the 367 isolates. Four prevalent capsular types, HS5/31 complex (n = 27, 18%), HS3 (n = 26, 17%), HS4A (n = 10, 7%), and HS8/17 (n = 10, 7%) covered almost 50% of the strains from enteritis patients and 43% of the isolates from controls. In combination, the CPS genotype and LOS class was not discriminative between cases and controls. Dominant capsular types previously identified in C. jejuni strains isolated from patients with Guillain-Barré syndrome in Bangladesh were rarely detected in strains isolated from the young children. A similar distribution was evident among enteritis- and control-related strains when comparison was done between CPS types and LOS classes. This is the first systematic study presenting the distribution of CPS genotypes of C. jejuni strains isolated in Bangladesh from children with diarrhea and controls, with capsular genotypes HS5/31 complex, HS3, HS4A, and HS8/17 being prevalent in both. In conclusion, systematic studies are required to develop a multivalent capsule-based vaccine for children in low-income countries.

In about one in a thousand cases, a Campylobacter jejuni infection results in the severe polyneuropathy Guillain-Barré syndrome (GBS). It is established that sialylated lipo-oligosaccharides (LOS) of C. jejuni are a crucial virulence factor in GBS development. Frequent detection of C. jejuni with sialylated LOS in stools derived from patients with uncomplicated enteritis implies that additional bacterial factors should be involved. To assess whether the polysaccharide capsule is a marker for GBS, the capsular genotypes of two geographically distinct GBS-associated C. jejuni strain collections and an uncomplicated enteritis control collection were determined. Capsular genotyping of C. jejuni strains from the Netherlands revealed that three capsular genotypes, HS1/44c, HS2 and HS4c, were dominant in GBS-associated strains and capsular types HS1/44c and HS4c were significantly associated with GBS (p 0.05 and p 0.01, respectively) when compared with uncomplicated enteritis. In a GBS-associated strain collection from Bangladesh, capsular types HS23/36c, HS19 and HS41 were most prevalent and the capsular types HS19 and HS41 were associated with GBS (p 0.008 and p 0.02, respectively). Next, specific combinations of the LOS class and capsular genotypes were identified that were related to the occurrence of GBS. Multilocus sequence typing revealed restricted genetic diversity for strain populations with the capsular types HS2, HS19 and HS41. We conclude that capsular types HS1/44c, HS2, HS4c, HS19, HS23/36c and HS41 are markers for GBS. Besides a crucial role for sialylated LOS of C. jejuni in GBS pathogenesis, the identified capsules may contribute to GBS susceptibility., (Copyright © 2015 European Society of Clinical Microbiology and Infectious Diseases. All rights reserved.)

Campylobacter jejuni is the most important cause of antecedent infections leading to Guillain-Barré syndrome (GBS) and Miller Fisher syndrome (MFS). The objective of the present study was to define the genetic diversity, population structure, and potential role of poultry in the transmission of Campylobacter to humans in Bangladesh. We determined the population structure of C. jejuni isolated from poultry (n = 66) and patients with enteritis (n = 39) or GBS (n = 10). Lipooligosaccharide (LOS) typing showed that 50/66 (76 %) C. jejuni strains isolated from poultry could be assigned to one of five LOS locus classes (A-E). The distribution of neuropathy-associated LOS locus classes A, B, and C were 30/50 (60 %) among the typable strains isolated from poultry. The LOS locus classes A, B, and C were significantly associated with GBS and enteritis-related C. jejuni strains more than for the poultry strains [(31/38 (82 %) vs. 30/50 (60 %), p < 0.05]. Multilocus sequence typing (MLST) defined 15 sequence types (STs) and six clonal complexes (CCs) among poultry isolates, including one ST-3740 not previously documented. The most commonly identified type, ST-5 (13/66), in chicken was seen only once among human isolates (1/49) (p < 0.001). Amplified fragment length polymorphism (AFLP) revealed three major clusters (A, B, and C) among C. jejuni isolated from humans and poultry. There seems to be a lack of overlap between the major human and chicken clones, which suggests that there may be additional sources for campylobacteriosis other than poultry in Bangladesh.

Background: Campylobacter jejuni is the predominant antecedent infection in Guillain-Barré syndrome (GBS). Molecular mimicry and cross-reactive immune responses to C. jejuni lipo-oligosaccharides (LOS) precipitate the development of GBS, although this mechanism has not been established in patients from developing countries. We determined the carbohydrate mimicry between C. jejuni LOS and gangliosides, and the cross-reactive antibody response in patients with GBS in Bangladesh., Methodology: Sera from 97 GBS patients, and 120 neurological and family controls were tested for antibody reactivity against LOS from C. jejuni isolates from GBS patients in Bangladesh (BD-07, BD-39, BD-10, BD-67 and BD-94) by enzyme-linked immunosorbent assay (ELISA). Cross-reactivity to LOS was determined by ELISA. The LOS outer core structures of C. jejuni strains associated with GBS/MFS were determined by mass spectrometry., Principle Findings: IgG antibodies to LOS from C. jejuni BD-07, BD-39, BD-10, and BD-67 IgG antibodies were found in serum from 56%, 58%, 14% and 15% of GBS patients respectively, as compared to very low frequency (<3%) in controls (p<0.001). Monoclonal antibodies specific for GM1 and GD1a reacted strongly with LOS from the C. jejuni strains (BD-07 and BD-39). Mass spectrometry analysis confirmed the presence of GM1 and GD1a carbohydrate mimics in the LOS from C. jejuni BD-07 and BD-39. Both BD-10 and BD-67 express the same LOS outer core, which appears to be a novel structure displaying GA2 and GD3 mimicry. Up to 90-100% of serum reactivity to gangliosides in two patients (DK-07 and DK-39) was inhibited by 50 µg/ml of LOS from the autologous C. jejuni isolates. However, patient DK-07 developed an anti-GD1a immune response while patient DK-39 developed an anti-GM1 immune response., Conclusion: Carbohydrate mimicry between C. jejuni LOS and gangliosides, and cross-reactive serum antibody precipitate the majority of GBS cases in Bangladesh.

Background: Campylobacter jejuni enteritis is the predominant bacterial infection preceding Guillain-Barré syndrome (GBS), an acute postinfectious immune-mediated polyradiculoneuropathy. The purpose of this study was to define the clinical phenotype of GBS and the relation with preceding C jejuni infections in Bangladesh., Methods: We performed a prospective matched case-control hospital surveillance including 100 patients fulfilling the National Institute of Neurological Disorders and Stroke criteria for GBS from 2006 to 2007 in the Dhaka area of Bangladesh. Detailed clinical, electrophysiologic, serologic, and microbiologic data were obtained with a follow-up of 6 months., Results: GBS affected predominantly young adult males living in rural areas. Sixty-nine percent of the patients had clinical evidence of a preceding infection. The most frequent symptom was diarrhea (36%). The majority of patients had a pure motor variant of GBS (92%) with relatively infrequent cranial nerve involvement (30%). Twenty-five percent of patients required respiratory support. Electrophysiologic studies showed that 67% of patients had an axonal variant of GBS. Eleven patients (14%) died, and 23 (29%) remained severely disabled during the follow-up. Positive C jejuni serology was found in an unprecedented high frequency of 57% as compared with 8% in family controls and 3% in control patients with other neurologic diseases (p < 0.001). C jejuni infection was significantly associated with serum antibodies to the gangliosides GM1 and GD1a, axonal neuropathy, and greater disability., Conclusions: We report an unusually high frequency of the axonal variant of Guillain-Barré syndrome in Bangladesh, associated with preceding Campylobacter jejuni infection, severe residual disability, and high mortality.

Background: Campylobacter jejuni is a common cause of acute gastroenteritis and is associated with post-infectious neuropathies such as the Guillain-Barré syndrome (GBS) and the Miller Fisher syndrome (MFS). We here present comparative genotyping of 49 C. jejuni strains from Bangladesh that were recovered from patients with enteritis or GBS. All strains were serotyped and analyzed by lipo-oligosaccharide (LOS) genotyping, amplified fragment length polymorphism (AFLP) analysis, multilocus sequence typing (MLST), and pulsed-field gel electrophoresis (PFGE)., Methodology/principal Findings: C. jejuni HS:23 was a predominant serotype among GBS patients (50%), and no specific serotype was significantly associated with GBS compared to enteritis. PCR screening showed that 38/49 (78%) of strains could be assigned to LOS classes A, B, C, or E. The class A locus (4/7 vs 3/39; p<0.01) was significantly associated in the GBS-related strains as compared to enteritis strains. All GBS/oculomotor related strains contained the class B locus; which was also detected in 46% of control strains. Overlapping clonal groups were defined by MLST, AFLP and PFGE for strains from patients with gastroenteritis and GBS. MLST defined 22 sequence types (STs) and 7 clonal complexes including 7 STs not previously identified (ST-3742, ST-3741, ST-3743, ST-3748, ST-3968, ST-3969 and ST-3970). C. jejuni HS:23 strains from patients with GBS or enteritis were clonal and all strains belonged to ST-403 complex. Concordance between LOS class B and ST-403 complex was revealed. AFLP defined 25 different types at 90% similarity. The predominant AFLP type AF-20 coincided with the C. jejuni HS:23 and ST-403 complex., Conclusion/significance: LOS genotyping, MLST, AFLP and PFGE helped to identify the HS:23 strains from GBS or enteritis patients as clonal. Overall, genotypes exclusive for enteritis or for GBS-related strains were not obtained although LOS class A was significantly associated with GBS strains. Particularly, the presence of a clonal and putative neuropathogenic C. jejuni HS:23 serotype may contribute to the high prevalence of C. jejuni related GBS in Bangladesh.

From 300 stool samples, 58 Campylobacter strains were isolated by standard microbiological and biochemical methods. Of these, 40 strains were identified as Campylobacter jejuni and 5 as Campylobacter coli. The presence of flaA (100%), cadF (100%), racR (100%), dnaJ (100%), pldA (100%), ciaB (95%), virB11 (0%), ceuE (82.5%), cdtA (97.5%), cdtB (97.5%), cdtC (97.5%), and wlaN (7.5%) genes was detected in C. jejuni by PCR. All C. jejuni strains but one produced cytolethal distending toxin in a HeLa cell assay.

Background: Bangladesh has achieved a remarkable success with the eradication of poliomyelitis. However, non-polio acute flaccid paralysis and its clinical presentation as the Guillain-Barré syndrome (GBS) is still frequently diagnosed. GBS has a diverse clinical phenotype that varies according to geography. Campylobacter jejuni enteritis is the predominant bacterial infection preceding GBS. The purpose of the study was to define the clinical phenotype of GBS and the relation with preceding C. jejuni infection and antiganglioside antibodies (GM1, GD1 and GQ1b) in a large GBS cohort from Bangladesh. Methods & Materials: We conducted a hospital based observational study including 403 patients fulfilling the National Institute of Neurological Disorders and stroke (NINDS) criteria for GBS patients between 2010 and 2013 in Dhaka Medical College Hospital, Dhaka, Bangladesh. Detailed clinical, electrophysiological, serologic and microbiological data were obtained. Results: GBS affected predominantly in young adults males (M/F = 2:1) living in rural areas. Antecedent events were recorded in 76% of patients. The most frequent events being gastroenteritis (46%) and upper respiratory tract infection (18%). Sixty-five percent of the patients were bed-bound (Hugh's F-score, 4) at entry and 17% patients required mechanical ventilator (F-score 5). Electrophysiological studies showed that 54% of patients had an axonal variant of GBS. About 90% patients did not receive specific treatment either Intravenous Immunoglobulin (IVIg) or plasmapheresis due to high expensive treatment cost. After 6 months follow up, 13% patients had died and 15% were still disabled. Evidence for a recent C. jejuni infection was found in 55% of GBS patients. In a GBS-associated strains collection from Bangladesh, capsular types HS23/36c, HS19, and HS41 were most prevalent. MLST analysis showed that HS19 (ST-22), HS23 (ST-3219) and HS41 (ST-362) were prevalent. Antiganglioside antibodies (GM1, GD1a and GQ1b) were frequently detected in GBS patients. Conclusion: GBS in Bangladesh is a severe, predominantly pure motor and axonal neuropathy with a high mortality rate. Recent C. jejuni infection and anti-ganglioside antibodies accounted for a significant proportion of GBS. Majority of the patients do not receive specific and standard treatment.with IVIg in view of its high price. Therefore, low-cost treatment strategies are required for GBS patients in developing countries. [ABSTRACT FROM AUTHOR]

Campylobacter jejuni is the leading cause of gastroenteritis and associated with Guillain-Barré syndrome (GBS) in both developed and developing countries. We provided distinct genomic features of a highly pathogenic C. jejuni strain, BD-67, associated with severe axonal variant of GBS. C. jejuni BD-67 strain was isolated from stool sample of GBS patient in Bangladesh and sequenced in Illumina NextSeq-500 platform. The genome was analyzed using multiple bioinformatics approaches. Auto-antibodies were measured by enzyme-linked immunosorbent assays (ELISAs). C. jejuni BD-67 was associated with severe axonal form of GBS (GBSDS 4; [bed bound] with ophthalmoplegia and reached nadir on day 6. Patient was serologically positive for C. jejuni LOS, GM1, GD1a, and GQ1b antibodies. C. jejuni BD-67 genome exhibited uniqueness in potential virulent genes of lipooligosaccharide (LOS) region, phage integration, and glycosyltransferase genes. BD-67 strain exhibited penner-serotype HS:23 and LOS class B. In-silico multilocus sequence typing (MLST) exhibited BD-67 belongs to sequence-type ST-985 and clonal complex ST-403 that appeared as the most diverse node in MLST-based minimum spanning tree analysis. Comparative analysis of LOS cluster and its components demonstrated that the β-1,3-glycosyltransferase and β-1,4-N-acetylgalactosaminyltransferase genes of LOS were truncated and produce 3 & 2 truncated complete DNA sequences (CDSs), respectively. The cstII gene was highly diversified with amino acid identity of 90.41% and belongs to a distinct clade with BD-10 in global phylogeny. BD-67 strain harbored 2 C. jejuni integrated elements (CJIE1 and CJIE3) which is rare in GBS-associated C. jejuni strains. Pangenomic analysis unveiled the presence of a unique genomic region in BD-67 which encoded different glycosyltransferase genes, phage integration (int A), flagellar protein (flg E_1). The atypical virulence factors, truncated CDSs of LOS cluster, and different unique structural genes of BD-67 might be associated with the severe form of GBS. Multi-omics study may unveil the key of C. jejuni associated GBS pathogenesis and severity. [ABSTRACT FROM AUTHOR]

Lipo-oligosaccharide (LOS) is the most important virulence factor of Campylobacter jejuni that structurally mimics human nerve ganglioside and consequently triggers Guillain-Barre´ syndrome (GBS) as a post-infectious sequela of gastroenteritis. We investigated the variations within the genomic content of LOS in C. jejuni isolated from patients with GBS or enteritis to find out their contribution to GBS induction. Seven GBS-associated C. jejuni strains were isolated and sequenced using Illumina NextSeq platform. We analyzed LOS-region of GBS-associated C. jejuni strains (n =7, Bangladesh ; n =10, Peru, USA, Netherlands) with respect to enteritis-associated strains (n =16, Bangladesh, Netherlands & Canada) and reference genome C. jejuni NCTC11168 using bioinformatics pipelines. The frequency of nucleotide-variation within LOS region of C. jejuni was substantially greater in GBS-associated strains than enteritis-associated strains (p =0.002). However, no unique single-nucleotide polymorphism (SNP), multiple-nucleotide polymorphism (MNP), or complexes of SNPs were detected in GBS-associated genes (cgtA, cgtB, cstII, cstIII, and wlaN). The cst-II gene (n=15) was predominant in GBS-associated strains compared to cst-III gene (n =2). The cst-II (Thr51) gene was frequently present in GBS-associated strains of Bangladesh, USA, and Netherlands with expression of GM1/GD1 epitope (78%), whereas those with cst-II (Asn51) had the GA2 and GD3 epitopes. cst-II (Asn51) was common in Peruvian strains. Peruvian strains isolated from acute motor axonal neuropathy (AMAN) variant were identical and closely related to 2 strains of AMAN variant from Bangladesh. Phase variable (PV) genes were prevalent in LOS-regions of Bangladeshi and Canadian strains. Among the 34 PV genes possessing repeat tracts, most short sequence repeats were identified as poly-G while five were poly-T and one poly-TA. The frequency of cst-II (Thr51) gene and nucleotide-variation were higher within LOS locus of GBS-associated C. jejuni. Our results support that genetic polymorphism of C. jejuni modifies the substrate specificity of LOS biosynthesis enzyme and autoantibody reactivity that determines the clinical presentation of GBS. [ABSTRACT FROM AUTHOR]