Case Of Persistent Infection Research Articles

Treatment of Fracture-Related Infection after Pelvic Fracture.

The management of pelvic fractures is a significant challenge. Surgical site infection can result in the need for revision surgery, cause functional impairment, and lead to a prolonged length of stay and increased treatment costs. Although reports on fracture-related infection (FRI) after pelvic fracture fixation are sparsely reported in the literature, it is a serious complication. This study analysed patients with FRIs after pelvic fracture regarding patient characteristics, treatment strategies, and an evaluation of risk factors for FRI. In this retrospective single-centre study, FRI was diagnosed based on clinical symptoms of infection and a positive culture of a bacterial infection. Depending on the severity and acuteness of the infection, osseous stabilization was restored either via implant retention (stable implant, no osteolysis), exchange (loose implant or bony defect), or external fixation (recurrence of infection after prior implant retaining revision). Healing of infection was defined as no sign of recurring infection upon clinical, radiological, and laboratory examination in the last follow-up visit. The FRI rate in our patient population was 7.5% (24/316). In 8/24 patients, the FRI occurred within the first three weeks after initial surgery (early) and 16/24 presented with a late onset of symptoms of FRI. A strategy of debridement, antibiotics, and implant retention (DAIR) was successful in 9/24 patients with FRI after pelvic fracture. A total of 10 patients required an exchange of osteo-synthetic implants, whereof three were exchanged to an external fixator. In five patients, we removed the implant because the fracture had already consolidated at the time of revision for infection. A total of 17/24 patients had a poly-microbial infection after a pelvic fracture and 3/24 patients died from post-traumatic multi-organ failure within the first 6 months after trauma. There were no cases of persistent infection within the remaining 21 patients. Although poly-microbial infection is common in FRI after pelvic fracture, the recurrence rate of infection is relatively low. A complex pelvic trauma with significant soft tissue injury is a risk factor for recurrent infection and multiple revisions. A strategy of DAIR can be successful in patients with a stable implant. In cases with recurrent infection or an unstable fracture site, the exchange of implants should be considered.

Persistent SARS-CoV-2 Infection in a Patient With Non-hodgkin Lymphoma: Intra-Host Genomic Diversity Analysis

The severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has caused a pandemic, threatening global public health. Several cases of persistent infection have been described, but there are few reports that compared the genetic variability among samples collected from the patient during infection. In the current study, we reported a viral genetic analysis of a diabetic male patient with Non-Hodgkin Lymphoma affected by persistent SARS-CoV-2 infection. We sequenced the patient-derived viral isolated both from oro/nasopharyngeal swab and VeroE6 cell line, collected from the same patient at different points of the infection. Due to the insufficient material of the second swab received, in order to obtain a complete coverage of the viral genome, it was convenient to perform a virus isolation after cell culture. Both genomes belonged to Pangolin Lineage B.1, Nextstrain clade 20A and GISAID clade G. The mutation spectrum predicted for the two viral genomes reveal three additionally mutations in the sequence of second sample when compared with mutations set identified in the first sample. Our findings show the evolution of the intra-host variability during the course of a long-lasting infection.

Nanovaccines against Animal Pathogens: The Latest Findings.

Nowadays, safe and efficacious vaccines represent powerful and cost-effective tools for global health and economic growth. In the veterinary field, these are undoubtedly key tools for improving productivity and fighting zoonoses. However, cases of persistent infections, rapidly evolving pathogens having high variability or emerging/re-emerging pathogens for which no effective vaccines have been developed point out the continuing need for new vaccine alternatives to control outbreaks. Most licensed vaccines have been successfully used for many years now; however, they have intrinsic limitations, such as variable efficacy, adverse effects, and some shortcomings. More effective adjuvants and novel delivery systems may foster real vaccine effectiveness and timely implementation. Emerging vaccine technologies involving nanoparticles such as self-assembling proteins, virus-like particles, liposomes, virosomes, and polymeric nanoparticles offer novel, safe, and high-potential approaches to address many vaccine development-related challenges. Nanotechnology is accelerating the evolution of vaccines because nanomaterials having encapsulation ability and very advantageous properties due to their size and surface area serve as effective vehicles for antigen delivery and immunostimulatory agents. This review discusses the requirements for an effective, broad-coverage-elicited immune response, the main nanoplatforms for producing it, and the latest nanovaccine applications for fighting animal pathogens.

Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) Sequence Characteristics of Coronavirus Disease 2019 (COVID-19) Persistence and Reinfection.

BackgroundBoth severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) reinfection and persistent infection have been reported, but sequence characteristics in these scenarios have not been described. We assessed published cases of SARS-CoV-2 reinfection and persistence, characterizing the hallmarks of reinfecting sequences and the rate of viral evolution in persistent infection.MethodsA systematic review of PubMed was conducted to identify cases of SARS-CoV-2 reinfection and persistence with available sequences. Nucleotide and amino acid changes in the reinfecting sequence were compared with both the initial and contemporaneous community variants. Time-measured phylogenetic reconstruction was performed to compare intrahost viral evolution in persistent SARS-CoV-2 to community-driven evolution.ResultsTwenty reinfection and 9 persistent infection cases were identified. Reports of reinfection cases spanned a broad distribution of ages, baseline health status, reinfection severity, and occurred as early as 1.5 months or >8 months after the initial infection. The reinfecting viral sequences had a median of 17.5 nucleotide changes with enrichment in the ORF8 and N genes. The number of changes did not differ by the severity of reinfection and reinfecting variants were similar to the contemporaneous sequences circulating in the community. Patients with persistent coronavirus disease 2019 (COVID-19) demonstrated more rapid accumulation of sequence changes than seen with community-driven evolution with continued evolution during convalescent plasma or monoclonal antibody treatment.ConclusionsReinfecting SARS-CoV-2 viral genomes largely mirror contemporaneous circulating sequences in that geographic region, while persistent COVID-19 has been largely described in immunosuppressed individuals and is associated with accelerated viral evolution.

Evaluation of Infection after Anterior Cruciate Ligament Reconstruction during a Short Period.

PurposeWe encountered 7 cases (7.1%) of infection (5 deep and 2 superficial) in 98 cases of anterior cruciate ligament (ACL) reconstruction using hamstring autografts in a 17-month period. The aim of this study was to analyze the causes of infection and to introduce our treatment strategy.Materials and MethodsWe investigated the shelf-life of the fixation implants, the order of surgery, previous knee surgery, infectious pathogen, treatment of infection, and results of treatment.ResultsThere was no problem with the expiration date of the fixation implants. The order of surgery was either the last or second to the last of all those performed on the same day. One patient had undergone knee surgery 8 months previously. The treatment after infection included aggressive debridement in all cases. Revision ACL reconstruction with graft removal was performed in 1 case of persistent infection with methicillin-resistant Staphylococcus aureus. All cases had satisfactory clinical results without recurrence during a mean 24.9 months of follow-up.ConclusionsWe could not verify the exact cause of the high incidence of infection during the 17-month period. However, preventive measures are important to decrease the incidence of infection after ACL reconstruction.

Single-stage revision for periprosthetic hip infection using antibiotic loaded impaction graft.

Staged revision for periprosthetic infection of the hip is an accepted and widely used technique by many surgeons. However, single-stage exchange of the hip prosthesis remains an attractive option to others because of the advantages of reduced morbidity, shorter treatment time and hospital stay in addition to the reduced cost of treatment. Single-stage revision for periprosthetic hip infection can achieve excellent results if a specific protocol for patients' selection and management is followed. 52 patients with evidence of periprosthetic infection had preoperative aspiration of the affected hip. The infecting organisms were identified in 33/52 and single-stage revision was performed. The remaining 19 patients had a 2-stage exchange arthroplasty. Patients in the single-stage revision protocol had antibiotic loaded morsellized bone graft, a cemented cup and a long cementless stem. At an average follow up of 6 (range 4-8) years postoperatively, only 1 case of persistent infection was found in the single-stage group - a 97% rate of eradicating infection was achieved. Single-stage exchange achieves excellent success rate in patients with periprosthetic infection when a specific protocol for patient selection and management is followed.

Single-stage versus two-stage revision of total hip replacement for contained periprosthetic infection

Objective In this article, single-stage exchange arthroplasty for periprosthetic hip infection was compared with the two-stage revision protocol in patients without draining sinuses. Background Staged revision for periprosthetic infection of the hip is an accepted and widely used technique by many surgeons. However, single-stage exchange of the hip prosthesis remains an attractive option to some. Patients and methods Fifty-two patients with evidence of periprosthetic infection underwent preoperative aspiration of the affected hip. The organism was identified in 33/52 patients, and single-stage revision was performed. The remaining 19 patients underwent two-stage exchange arthroplasty. All patients had cemented cup and long cementless stem. Results At an average 4 years (range: 2–7 years) postoperatively, only one case of persistent infection was found in the single-stage group, which showed a success rate of 97%, in comparison with 95% success rate in the staged protocol. Conclusion Single-stage exchange achieves excellent success rates in patients with contained infection when the organism is identified preoperatively.

Safety and Efficacy of Pedicle Screws and Titanium Mesh Cage in the Treatments of Tuberculous Spondylitis of the Thoracolumbar Spine

Study DesignThis is a retrospective series.PurposeWe wanted to analyze the safety and effectiveness of using the newer generation metallic implants (pedicle screws and/or titanium mesh) for the treatment of tuberculous spondylitis.Overview of the LiteratureThere have been various efforts to prevent the development of a kyphotic deformity after the treatment of tuberculous spondylitis, including instrumentation of the spine. Pedicle screws and titanium mesh cages have become more and more popular for treating various spinal problems.MethodsTwenty two patients who had tuberculous spondylitis were treated with anterior radical debridement and their anterior column of spine was supported with a tricortical iliac bone graft (12 patients) or by mesh (10 patients). Supplementary posterior pedicle screw instrumentation was performed in 17 of 22 patients. The combination of surgeries were anterior strut bone grafting and posterior pedicle screws in 12 patients, anterior titanium mesh and posterior pedicle screws in 5 patients and anterior mesh only without pedicle screws in 5 patients. The patients were followed up with assessing the laboratory inflammatory parameters, the serial plain radiographs and the neurological recovery.ResultsThe erythrocyte sedimentation rate and C-reactive protein levels were eventually normalized and there was no case of persistent infection or failure to control infection in spite of a mettalic implant in situ. The overall correction of kyphotic deformity was initially 8.9 degrees, and the loss of correction was 6.2 degrees. In spite of some loss of correction, this technique effectively prevented clinically significant kyphotic deformity. The preoperative Frankel grades were B for 1 patient, C for 4, D for 4 and E for 13. At the final follow-up, 7 of 9 patients recovered completely to Frankel grade E and only two patients showed a Frankel grade of D.ConclusionsStabilizing the spine with pedicle screws and/or titanium mesh in patients with tubercuous spondylitis effectively prevents the development of kyphotic deformity and this did not prevent controlling infection when this technique was combined with radical debridement and anti-tuberculous chemotherapy.

Evidence for lack of cross-genotype protection of CD4+ T cell responses during chronic hepatitis C virus infection.

CD4+ T lymphocyte responses are thought to play a major role in control of the hepatitis C virus (HCV). Few, however, have been mapped down to the level of peptide and HLA restriction. Furthermore, the ability of such T cells to respond to viruses which differ in genotype has not been addressed in detail. In most cases of persistent infection with HCV, CD4 proliferative responses are weak or absent. From a large cohort of persistently infected patients, we identified an individual with unusually robust and persistent responses in the face of chronic infection. We firstly mapped two peptide epitopes to regions of the nonstructural protein NS4 (aa1686-1705 and aa 1746-1765). However, in contrast to the genotype 1a derived antigens used for mapping, the infecting virus was identified as genotype 3a. Strikingly, the patient's CD4 response to these epitopes were specific only for the genotype 1a sequence, and did not recognize genotype 3a synthetic peptides. Serologic assays indicated that prior exposure to HCV of genotype 1 had occurred. This patient therefore maintains strong CD4 proliferative responses which are genotype specific and not cross-reactive. The apparent 'misdirection' of these nonprotective responses has important implications for the role of natural and vaccine induced CD4 responses in the face of variable viruses.

Safety and Efficacy of Metalic Implants in the Treatments of Tuberculous Spondylitis

Study Design: A retrospective study Objective: To analyze the safety and effectiveness of treatments using metallic implants in the tuberculous spondylitis. Summary of Literature Review: Residual kyphosis and loss of correction remain the major problems following surgery for tuberculous spondylitis. Several authors have used metallic implants for the prevention of these complications. However, the safety of metallic implants use in tuberculous spine infections are still controversial. Materials and Methods: Seventeen patients, who underwent surgery, and were stabilized by the use of a metallic implant for tuberculous spondylitis, and followed up for more than 1 year were included in this study. All patients were treated with combined anterior fusion (with or without mesh) and/or posterior pedicle screw instrumentation. The patients were followed up with serial plain radiographs, laboratory inflammatory parameters and neurological recovery. Results: The overall correction of the kyphotic deformity was initially 8.5 degrees, and loss of correction occurred at 5.8 degrees. Although some loss of correction occurred, even after the use of a metallic implant, clinically significant kyphotic deformity was effectively prevented. There were no cases of persistent infection or failure to control infection when the metallic implantation was combined with an anterior radical debridement and chemotherapy. The erythrocyte sedimentation rate and C-reactive protein were eventually normalized in all patients. The preoperative neurological deficits were: incomplete paralysis in 9 cases and radiculopathy in 4. At the final follow-up, 11 cases had completely recovered, partial residual neurological deficits remaining in 2. C o n c l u s i o n s: The use of instrumentation with metallic implants, in tubercuous spondylitis of the spine, provided immediate stability, and did not prohibit the control of infection when combined with radical debridement and anti-tuberculous chemotherapy.

Molecular variants of human papillomavirus types 16 and 18 preferentially associated with cervical neoplasia

In order to determine geographically related intratypic variation in human papillomavirus (HPV) type 16 and 18 isolates that could be associated with lesion development, data were analysed from an ongoing cohort study of the natural course of infection of HPVs and cervical neoplasia. Testing for HPVs was carried out by PCR and molecular variants of these HPVs were characterized by sequence analysis of the long control region and by dot blot hybridization of the E6 and L1 genes. Tests for HPV were done in multiple first-year specimens from 1690 women enrolled in a cancer screening program from 1993 to 1997. Subjects were followed-up by cytology and cervicography for detection of cervical lesions. Seven variants of HPV-16 and four of HPV-18 were detected in one or more specimens from 65 subjects. The same variant was found in specimens taken on different visits from each case of persistent infection. Overall, non-European variants tended to persist more frequently [odds ratio (OR)=4.5; 95% confidence interval (CI), 1.6-12.4] than European (E) variants (OR=2.5; 95% CI, 1.3-4.9), relative to the risk of persistence for non-oncogenic HPVs. In addition, non-E variants were more strongly associated with risk of both prevalent (age- and race-adjusted OR=172.2; 95% CI, 47.1-630.1) and incident [relative risk (RR)=22.5; 95% CI, 6.0-83.9] high-grade lesions than E variants (prevalent lesions OR=46.3; 95% CI, 15.5-138.0 and incident lesons RR=6.1; 95% CI, 1.3-27.4), relative to the risk for HPV-negative women. Although consistent, the latter differences were not statistically significant. If confirmed in other populations, measurement of intratypic variation of HPV-16 and -18 has the potential to serve as an ancillary tool in cervical cancer screening.

The molecular epidemiology of parvovirus B19

Parvovirus B19, the only known parvovirus pathogenic for humans, is a common infectious agent, causing erythema infectiosum in children, post-infection arthropathy in adults, transient aplastic crisis in patients with shortened red cell survival and chronic bone marrow failure in immunosuppressed patients. B19 infection has also been associated with a diverse group of clinical manifestations including hydrops fetalis, congenital red cell aplasia, vasculitis syndromes, glomerulonephritis with nephrotic syndrome, meningitis, encephalopathy, peripheral neuropathy, myocarditis and hepatitis. B19 does not propogate well in conventional cell culture but B19 DNA from clinical samples has been amplified using molecular cloning or PCR. Analysis of isolates has revealed genetic diversity, and a workable strategy for strain classification has been devised to study the molecular epidemiology of B19 infection. The particular genotype endemic in Japan during the outbreak of 1981–1982 was replaced in the outbreak of 1986–1987 by a different genotype similar to B19 strains isolated in the USA and Europe during 1978–1986, suggesting the possibility of global transmission of B19. Sequence heterogeneity between B19 strains isolated from each case of persistent infection (infected fetuses and a persistently-infected patient with arthralgia and chronic fatigue syndrome) is probably accounted for by the many rounds of replication necessary to maintain a prolonged infection. Isolation of a new B19 genotype from a particular disease (e.g. encephalopathy) and replacement of genotype during persistent infection would seem to be the platform from which to launch further studies to associate particular genotypes with particular clinical manifestations of infection.

Rufloxacin once daily in acute exacerbations of chronic bronchitis

In this open study the efficacy and tolerability of rufloxacin in a single dose of 400 mg the first day and 200 mg the nine consecutive days was studied in 26 patients with an acute exacerbation of chronic bronchitis. Twenty-two patients were evaluable for efficacy. Four patients stopped treatment prematurely after five days because of clinical cure. At the enrollment visit a pathogen was isolated in the sputum sample in 19 of 22 evaluable patients. The predominant pathogens were Streptococcus pneumoniae and Moraxella catarrhalis. In 17 of these 19 bacteriologically evaluable patients the initial infecting organism was eradicated from specimens obtained within 48 hours after the end of therapy. There was one case of persistent infection caused by S. pneumoniae (MIC 4 mg/l), one patient had a superinfection with Serratia marcescens (MIC 1 mg/l) susceptible to rufloxacin and therapy was stopped after five days due to clinical failure. One week after the end of therapy, 15 patients remained free from infection whilst one patient experienced reinfection with Klebsiella pneumoniae (MIC 0.5 mg/l). Clinical cure or improvement was observed in 21 of 22 patients. Mild adverse events were reported by two of 26 enrolled patients. In one patient, complaining of headache and dizziness, the adverse events were considered possibly study drug related. No abnormal laboratory findings were reported. Nadir plasma levels of rufloxacin were measured and no accumulation in plasma was observed during treatment. A ten day course of an oral single dose of rufloxacin proved efficacious and was well tolerated in patients with an acute exacerbation of chronic bronchitis.(ABSTRACT TRUNCATED AT 250 WORDS)

Ciprofloxacin therapy of urinary tract infections in paraplegic and tetraplegic patients: a bacteriological assessment

The efficacy of a 250 mg dose of oral ciprofloxacin twice daily for five days was studied in the treatment of urinary tract infection in paraplegic and tetraplegic patients. Thirty-eight patients completed the study. By day 3 of therapy the infecting organisms had been eradicated from the urine in 97.2% of the patients. Follow-up, post-therapy samples on day 14 showed 66.7% positive culture results and by day 35, 92.0% were positive. The ciprofloxacin therapy proved efficacious in 97.2% of the patients; however, the factors that predisposed this group of patients to urinary tract infections still persisted and reinfection or superinfection occurred in 92.0%. There was one case of persistent infection caused by Enterococcus faecalis.