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Cureus Jun 2022Eculizumab, first-line therapy for paroxysmal nocturnal hemoglobinuria (PNH) and atypical hemolytic uremic syndrome (aHUS), has infectious side effects in addition to... (Review)
Review
Eculizumab, first-line therapy for paroxysmal nocturnal hemoglobinuria (PNH) and atypical hemolytic uremic syndrome (aHUS), has infectious side effects in addition to its therapeutic benefits. This study aims to discuss the mechanism of development of infections, prevention, and timely treatment to prevent complications such as septic shock and mortality. The study was conducted using the Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA) checklist and reporting guidelines for systematic review. Inclusion and exclusion criteria were determined. A total of 10 research papers were extracted after exploring Pubmed and Google Scholar from 2001 to 2021. The New Castle Ottawa Questionnaire for non-randomized clinical trials and the National Institutes of Health (NIH) quality assessment tool for case reports and case series were used to assess the risk of bias. The studies included in this systematic review describe infections with , , unusual species, , and . The main goal of this review is to impress upon the seriousness of the infectious complications associated with eculizumab. Health care providers should maintain a high index of suspicion for early identification and treatment.
PubMed: 35784997
DOI: 10.7759/cureus.25640 -
Open Medicine (Warsaw, Poland) 2020() is a Gram-negative bacterium, which rarely causes serious infection. This is a rare case report of acute glomerulonephritis diagnosed by pathological findings in a...
() is a Gram-negative bacterium, which rarely causes serious infection. This is a rare case report of acute glomerulonephritis diagnosed by pathological findings in a child accompanied by infection. The patient showed hematuria, proteinuria and hyperkalemia requiring emergency hemodialysis. After hospitalization, bacteremia became apparent. Pathological findings showed an increase in glomerulus inflammatory cells and glomerular C3 deposition was observed in the renal tissue biopsy. Final diagnosis was endocapillary proliferative glomerulonephritis. Clinical reports of infection requiring emergency hemodialysis in children are rare. Previous reports have suggested that lowered immune competency with chronic kidney disease may be a risk factor associated with serious invasive cases of infection. However, detailed clinical laboratory data and pathological findings have not been identified in previous case reports. Our case directly indicated complement activity and acute glomerulonephritis with infection. Although there are various causes for acute glomerulonephritis, infection-related glomerulonephritis (IRGN) is an important concept. infection might have a potential risk for IRGN with dysregulation of complement activity leading to serious and invasive clinical conditions than previously considered.
PubMed: 33313415
DOI: 10.1515/med-2020-0234 -
Clinical Medicine Insights. Pediatrics 2021, a low-virulence Gram-negative coccobacillus, is classically associated with conjunctivitis and upper respiratory tract infections; systemic infections such as sepsis...
, a low-virulence Gram-negative coccobacillus, is classically associated with conjunctivitis and upper respiratory tract infections; systemic infections such as sepsis have rarely been reported, especially in children. We describe a 28-month-old girl with atypical hemolytic uremic syndrome and stage II chronic kidney disease on long-term eculizumab therapy who presented with systemic inflammatory response syndrome and was found to have bloodstream infection. Eculizumab, a humanized monoclonal anti-C5 antibody, has been associated with susceptibility to infections with encapsulated bacteria, especially . This is the first report of an invasive bacterial infection with in a pediatric eculizumab recipient.
PubMed: 33613039
DOI: 10.1177/1179556521992367 -
Journal of Bacteriology Dec 1997Moraxella lacunata and Moraxella bovis use type 4 pili to adhere to epithelial tissues of the cornea and conjunctiva. Primer extension analyses were used to map the...
Moraxella lacunata and Moraxella bovis use type 4 pili to adhere to epithelial tissues of the cornea and conjunctiva. Primer extension analyses were used to map the transcriptional start sites for the genes encoding the major pilin subunits (tfpQ/I) and the DNA invertase (piv), which determines pilin type expression. tfpQ/I transcription starts at a sigma54-dependent promoter (tfpQ/Ip2) and, under certain growth conditions, this transcription is accompanied by weaker upstream transcription that starts at a potential sigma70-dependent promoter (tfpQ/Ip1). piv is expressed in both M. lacunata and M. bovis from a putative sigma70-dependent promoter (pivp) under all conditions assayed. Sigma54-dependent promoters require activators in order to initiate transcription; therefore, it is likely that tfpQ/Ip2 is also regulated by an activator in Moraxella. Primer extension assays with RNA isolated from Escherichia coli containing the subcloned pilin inversion region from M. lacunata showed that pivp is used for the expression of piv; however, tfpQ/Ip2 is not used for the transcription of tfpQ/I. Transcription from tfpQ/Ip2 was activated in E. coli when the sensor (PilS) and response regulator (PilR) proteins of type 4 pilin transcription in Pseudomonas aeruginosa were expressed from a plasmid. These results suggest that the expression of the type 4 pilin in M. lacunata and M. bovis is regulated not only by a site-specific DNA inversion system but also by a regulatory system which is functionally analogous to the PilS-PilR two-component system of P. aeruginosa.
Topics: Bacterial Outer Membrane Proteins; Bacterial Proteins; Base Sequence; DNA Nucleotidyltransferases; DNA-Binding Proteins; DNA-Directed RNA Polymerases; Escherichia coli; Escherichia coli Proteins; Fimbriae Proteins; Gene Expression Regulation, Bacterial; Integrases; Molecular Sequence Data; Moraxella; Moraxella bovis; Promoter Regions, Genetic; Pseudomonas aeruginosa; RNA Polymerase Sigma 54; Recombinases; Sigma Factor; Transcription Factors; Transcription, Genetic
PubMed: 9393693
DOI: 10.1128/jb.179.23.7298-7305.1997 -
Animals : An Open Access Journal From... Mar 2022From a clinical point of view, knowledge of the commensal microbial flora of the conjunctival sac in healthy individuals proves to be of great importance. The aim of...
From a clinical point of view, knowledge of the commensal microbial flora of the conjunctival sac in healthy individuals proves to be of great importance. The aim of this study was to assess the presence and the composition of normal ocular microflora of healthy donkeys. Fourteen clinically healthy donkeys () participated in the study. After prior ophthalmological examination, which showed no abnormalities, a conjunctival swab was taken from each donkey from the right and left eye. Species-specific identification was based on a morphological assessment of bacterial colonies stained with the Gram technique, as well as on biochemical properties and the disk-diffusion method. Around 82% of samples were positive for bacteria cultivation; was the most prevalently detected species, followed by . In conclusion, our study made it possible to determine the commensal flora of the conjunctival sac in donkeys. The obtained results also showed discrepancies in the composition of the conjunctival sac flora of donkeys and horses, despite the geographical proximity of performed studies. Knowledge of the commensal conjunctival flora of donkeys is of great clinical importance due to their greater exposure to corneal damage and infections than horses.
PubMed: 35327153
DOI: 10.3390/ani12060756 -
The Journal of Veterinary Medical... Dec 2018Although Moraxella lacunata causes conjunctivitis, keratitis, endocarditis, and otolaryngitis in humans, its infection is rare in animals. We report three cases of...
Although Moraxella lacunata causes conjunctivitis, keratitis, endocarditis, and otolaryngitis in humans, its infection is rare in animals. We report three cases of asymptomatic pulmonary abscesses caused by M. lacunata in zoo herbivores, including two elks (Cervus canadensis) and a common eland (Taurotragus oryx). In all cases, macroscopic findings included coalescence of lung lobes and severe pulmonary abscesses filled with cheese-like materials in cysts. Microscopic findings included pneumonia characterized by marked fibrin exudates in alveolar spaces and infiltration of inflammatory cells. M. lacunata was identified in bacterial cultures from pulmonary abscesses using biochemical API 20NE system. M. lacunata is rarely isolated from zoo animals; however, herein, we describe the first report of pulmonary abscesses caused by M. lacunata infection.
Topics: Animals; Animals, Zoo; Antelopes; Deer; Lung Abscess; Male; Moraxella; Moraxellaceae Infections
PubMed: 30369588
DOI: 10.1292/jvms.18-0455 -
Journal of Bacteriology Aug 1990Moraxella lacunata is a bacterium that is a causative agent of human conjunctivitis and keratitis. We have previously cloned the Q and I pilin (formerly called beta and... (Comparative Study)
Comparative Study
Moraxella lacunata is a bacterium that is a causative agent of human conjunctivitis and keratitis. We have previously cloned the Q and I pilin (formerly called beta and alpha pilin) genes of Moraxella bovis and determined that an inversion of 2 kilobases (kb) of DNA determines which pilin gene is expressed. Using an M. bovis pilin gene as a hybridization probe to screen a lambda ZAP library of M. lacunata DNA, we have isolated a clone that not only contains the entire type 4 pilin gene inversion region of M. lacunata but inverts the 2-kb region on a plasmid subclone (pMxL1) in Escherichia coli. Deletion derivatives of pMxL1 yielded some plasmids that still had the entire inversion region but were phase locked into one or the other of the two potential orientations. Similarly, insertions of a 2-kb streptomycin-resistant element (omega) within some regions outside of the inversion also resulted in phase-locked plasmids. These deletions and insertions thus localize a probable invertase necessary for the inversion event. The region was sequenced, and an open reading frame with over 98% DNA sequence homology to an open reading frame that we previously found in M. bovis and called ORF2 appeared to be a strong candidate for the invertase. This conclusion was confirmed when a plasmid containing the M. bovis ORF2 supplied, in trans, the inversion function missing from one of the M. lacunata phase-locked inversion mutants. We have named these putative invertase genes piv(ml) (pilin inversion of M. lacunata) and piv(mb) (pilin inversion of M. bovis). Despite previously noted sequence similarities between the M. bovis sites of inversion and those of the Hin family of invertible segments and a 60-base-pair region within the inversion with 50% sequence similarity to the cin recombinational enhancer, there is no significant sequence similarity of the Piv invertases to the Hin family of invertases.
Topics: Amino Acid Sequence; Bacterial Outer Membrane Proteins; Base Sequence; Chromosome Deletion; Chromosome Inversion; Cloning, Molecular; DNA Transposable Elements; DNA, Bacterial; Escherichia coli; Fimbriae Proteins; Fimbriae, Bacterial; Gene Library; Genes, Bacterial; Genetic Complementation Test; Molecular Sequence Data; Moraxella; Oligonucleotide Probes; Plasmids; Restriction Mapping; Sequence Homology, Nucleic Acid
PubMed: 1973927
DOI: 10.1128/jb.172.8.4370-4377.1990 -
Journal of Bacteriology Jul 1991The bacterium Moraxella lacunata is a causative agent of human conjunctivitis and keratitis. We have previously reported construction of plasmid pMxL1, which includes a... (Comparative Study)
Comparative Study
The bacterium Moraxella lacunata is a causative agent of human conjunctivitis and keratitis. We have previously reported construction of plasmid pMxL1, which includes a 5.9-kb fragment on which the pilin gene inversion region of M. lacunata resides. The inversion region of pMxL1 was shown to invert when pMxL1 was in an Escherichia coli host cell. In this report, we present Western immunoblot analysis using Moraxella bovis Epp63 anti-I and anti-Q pilin sera which demonstrate that pMxL1 makes pilin only when in orientation 1. The sequence of the pMxL1 plasmid containing the invertible region contains a perfect tandem repeat of 19 bp in the orientation 1 nonexpressed pilin gene at the middle of the recombination junction site. This 19-bp insert causes a frameshift and disrupts the pilin gene. The predicted amino acid sequence of this nonfunctional pilin gene (with the 19-bp repeat subtracted) bears closest resemblance to M. bovis Epp63 Q pilin sequence, although the other (functional) M. lacunata pilin encoded by pMxL1 shows slightly higher homology to Q pilin. Comparison of the pMxL1 sequence with that of the M. bovis Epp63 sequence shows two other particularly interesting differences. One is a 15-bp sequence addition found in pMxL1 at the 60-bp region previously reported as a possible M. bovis recombinational enhancer. The second is an AT deletion in pMxL1 compared with Epp63 within an open reading frame (tfpB) which results in the pMxL1 tfpB open reading frame being one-third shorter than in Epp63. The DNA sequences in these three altered regions from the M. lacunata strain from which pMxL1 was derived were amplified by polymerase chain reaction and sequenced. The parent strain was found to contain the differences seen in pMxL1. Comparison of the M.bovis and M. lacunata pilin gene amino acid sequences is also presented.
Topics: Amino Acid Sequence; Bacterial Outer Membrane Proteins; Base Sequence; Chromosome Inversion; Fimbriae Proteins; Genes, Bacterial; Molecular Sequence Data; Moraxella; Polymerase Chain Reaction; Repetitive Sequences, Nucleic Acid
PubMed: 2061282
DOI: 10.1128/jb.173.13.4000-4006.1991 -
Journal of Biochemistry Mar 1995A gene coding for protease II (basic amino acid specific oligoendopeptidase) from Moraxella lacunata was cloned and expressed in Escherichia coli DH1. The transformant...
A gene coding for protease II (basic amino acid specific oligoendopeptidase) from Moraxella lacunata was cloned and expressed in Escherichia coli DH1. The transformant harboring a hybrid plasmid, pMPROII-12, with a 3.0-kbp insert at the PvuII-SacI site in pUC19, showed 23-fold higher enzyme activity than M. lacunata. The expressed enzyme from E. coli DH1/pMPROII-12 was purified by 40-80% ammonium sulfate fractionation, chromatography on DEAE-Toyopearl, and Sephadex G-150 gel filtration. The enzyme was most active at pH 6.5 and stable at pH 6.5-9.5. It had an optimum temperature of 35 degrees C for 5 min of reaction and was stable to up to 35 degrees C for 30 min at pH 7.0. Its molecular weight was estimated to be 80,000 by SDS-PAGE and gel-filtration analyses. It enzyme was inhibited by diisopropyl fluorophosphate (DFP) and classified as a serine endoprotease. Its amino acid sequence was 38% homologous to that of the E. coli protease II. By alignment with other members of the prolyl endopeptidase family, the amino acid residues involved in the catalytic triad were deduced to be Ser-534, Asp-619, and His-654. The enzyme was crystallized by the hanging drop vapor diffusion method using PEG 4000 as precipitant.
Topics: Amino Acid Sequence; Base Sequence; Cloning, Molecular; Crystallization; Escherichia coli; Gene Expression Regulation, Bacterial; Gene Expression Regulation, Enzymologic; Genes, Bacterial; Metalloendopeptidases; Molecular Sequence Data; Moraxella; Recombinant Proteins; Substrate Specificity
PubMed: 7629037
DOI: 10.1093/oxfordjournals.jbchem.a124759 -
Scientific Reports Apr 2024Diabetes mellitus is recognized as a major predisposing factor for Moraxella keratitis. However, how diabetes mellitus contributes to Moraxella keratitis remains...
Diabetes mellitus is recognized as a major predisposing factor for Moraxella keratitis. However, how diabetes mellitus contributes to Moraxella keratitis remains unclear. In this study, we examined Moraxella keratitis; based on the findings, we investigated the impact of advanced glycation end products (AGEs) deposition in the cornea of individuals with diabetic mellitus on the adhesion of Moraxella isolates to the cornea. A retrospective analysis of 27 culture-proven cases of Moraxella keratitis at Ehime University Hospital (March 2006 to February 2022) was performed. Moraxella isolates were identified using matrix-assisted laser desorption ionization time-of-flight mass spectrometry. Among the patients, 30.4% had diabetes mellitus and 22.2% had the predominant ocular condition of using steroid eye drops. The species identified were Moraxella nonliquefaciens in 59.3% and Moraxella lacunata in 40.7% of patients. To investigate the underlying mechanisms, we assessed the effects of M. nonliquefaciens adherence to simian virus 40-immortalized human corneal epithelial cells (HCECs) with or without AGEs. The results demonstrated the number of M. nonliquefaciens adhering to HCECs was significantly increased by adding AGEs compared with that in controls (pā<ā0.01). Furthermore, in the corneas of streptozotocin-induced diabetic C57BL/6 mice treated with or without pyridoxamine, an AGE inhibitor, the number of M. nonliquefaciens adhering to the corneas of diabetic mice was significantly reduced by pyridoxamine treatment (pā<ā0.05). In conclusion, the development of Moraxella keratitis may be significantly influenced by the deposition of AGEs on the corneal epithelium of patients with diabetes mellitus.
Topics: Humans; Animals; Mice; Retrospective Studies; Diabetes Mellitus, Experimental; Pyridoxamine; Mice, Inbred C57BL; Keratitis; Moraxella; Cornea; Glycation End Products, Advanced
PubMed: 38580798
DOI: 10.1038/s41598-024-58659-7