Discordance between Serum Neutralizing Antibody Titers and the Recovery from COVID-19.

The recent pandemic of COVID-19 has caused a tremendous alarm around the world. Details of the infection process in the host have significant bearings on both recovery from the disease and on the correlates of the protection from the future exposures. One of these factors is the presence and titers of neutralizing Abs (NAbs) in infected people. In the current study, we set out to investigate NAbs in the recovered subjects discharged from the hospital in full health. Serum samples from a total of 49 documented consecutive COVID-19 subjects were included in the study. All the subjects were adults, and serum samples collected during the discharge were tested in viral neutralization, enzyme immunoassay (EIA), and Western immunoblot tests against viral Ags. Even though a majority of the recovered subjects had raised significant NAb titers, there is a substantial number of recovered patients (10 out of 49) with no or low titers of NAbs against the virus. In these cohorts as well as in patients with high NAb titers, viral Ag binding Abs were detectable in EIA tests. Both NAb titers and EIA detectable Abs are increased in patients experiencing a severe form of the disease, and in older patients the Ab titers were heightened. The main conclusion is that the recovery from SARS-CoV-2 infection is not solely dependent on high NAb titers in affected subjects, and this recovery process is probably produced by a complex interplay between many factors, including immune response, age of the subjects, and viral pathology.

Investigation of the changing etiology and risk factors of prosthetic joint infections : a university hospital surveillance study from 2011-2017.

We sought to characterize the causative pathogens of prosthetic joint infections (PJIs), evaluate the trends in microbial etiologies, and identify potential risk factors for PJI. This was a retrospective study analyzing 70 patients with PJI following 3,253 total joint arthroplasties between 2011 and 2017. Staphylococci were the most common cause of infection (52.9%). There was a significant trend in the percentage of carbapenem-resistant gram-negative bacilli (GNB) (increased to 66.7% in 2016 from 0.0% in 2011) (p=0.021). GNB and polymicrobial etiology were found at significantly high levels in cases involving early PJIs (p=0.005 and p=0.048, respectively). While staphylococci were significantly higher in PJIs after total knee arthroplasty (75%), GNB were significantly higher in PJIs after total hip arthroplasty (49.1%) (p<0.001 and p=0.001, respectively). Binary logistic regression analysis showed that the risk of PJI was significantly higher in cases with fracture and diabetes mellitus (odds ratio [OR], 4.3, 95% confidence interval [CI], 1.78-10.5 ; OR, 4.1, 95% CI, 1.66-10.5, respectively). These results suggest that the empirical and targeted antimicrobial treatment of PJIs may become more difficult in the future.

Analysis of infectious spondylodiscitis: 7-years data.

OBJECTIVE: Infectious spondylodiscitis (SD) is an infectious disease that is rare and difficult to diagnose due to its non-specific clinical features. In this study, we aimed to describe the clinical and diagnostic features of infectious spondylodiscitis. METHODS: All patients who were diagnosed with SD at our hospital during a 7-year period from January 1, 2011 through December 31, 2017 were included in the study. Spondylodiscitis is divided into the following three types: pyogenic, tuberculous, and brucellar. Clinical and laboratory data were collected retrospectively from the medical records of the patients. RESULTS: Of the 118 patients, 66 (55.9%) were female, 81 (68.6%) had pyogenic SD (PSD), 21 (17.8%) had tuberculous SD (TSD), and 16 (13.6%) had brucellar SD (BSD). The mean age was 59.3 ± 14.6 years. Leucocytosis was significantly higher in patients with PSD (p=0.01) than in patients with other types of SD. Thoracic involvement (47.6%) was significantly higher in patients with TSD (p=0.005) than in other patients. Sacral involvement (12.5%) was significantly higher in patients with BSD (p=0.01) than in other patients. Paravertebral abscess formation (42.8%) occurred most frequently in patients with TSD. Microbiologic agents were defined in 50% (18/36) of the surgical specimens and in 12.5% of the fine needle aspiration biopsy (FNAB) specimens. Staphylococcus aureus was the most common microbiological agent in patients with PSD. Spinal surgery was defined as a risk factor for PSD (p = 0.0001). Binary logistic regression analysis revealed that female gender, thoracic involvement and night sweats were the predictive markers for TSD (OR 4.5 [95% CI 1.3-15.3] and OR 5 [95% CI 1.7-14.6]). CONCLUSION: PSD is the most frequent form of SD. Leucocytosis is most common in patients with PSD. Thoracic involvement and paraspinal abscess were prominent in patients with TSD. Sacral involvement was most common in patients with BSD. Thoracic involvement, female gender and night sweats were the predictive markers for TSD. The microbiological culture positivity rate was higher in surgical specimens compared to FNAB specimens. The need for surgical treatment was most common in patients with TSD.

Results of Nucleos(t)ide Analog Treatment Discontinuation in Hepatitis B e-Antigen-Negative Chronic Hepatitis B: NUCSTOP Study.

BACKGROUND/AIMS: This study aims to investigate the effects of nucleos(t)ide analogs (NAs) discontinuation in eligible patients in accordance with the Asian Pacific Association for the Study of the Liver hepatitis B guideline and the factors affecting clinical and virological relapses. MATERIALS AND METHODS: In this prospectively designed study, hepatitis B e antigen (HBeAg)-negative chronic hepatitis B patients who were followed up between 2012 and 2019 were evaluated and 57 patients were included. All participants enrolled the study were HBeAgnegative status at NA initiation. RESULTS: The median age of the patients was 49 (29-72) years and 24 (42%) were females. The median treatment duration was 96 (36- 276) months and patients were followed for a median duration of 27 months. Sixteen patients had a previous history of NA switch, and thirteen of these patients had a history of lamivudine resistance. Thirty-eight of 57 patients (66%) developed an elevated hepatitis B virus deoxyribonucleic acid level of >2000 IU/mL at least once, defined as virological relapse and 23 (60%) of them, experienced clinical relapse. Thirty-one of 57 patients were re-treated during the follow-up, and hepatitis B surface antigen (HBsAg) loss occurred among 4 (7%) patients. All patients who experienced HBsAg loss had a history of lamivudine resistance (P = .002). CONCLUSION: Despite receiving NAs suppression therapy for a long time, HBsAg loss occurs rarely. Although it was not life-threatening, most patients experienced relapses and treatment should be restarted. In our study, whether it is a coincidence that all patients with HBsAg loss are patients in whom NAs are used sequentially due to lamivudine resistance is an issue that needs to be further investigated.

Evaluation of hepatitis B vaccine efficacy and factors affecting vaccine nonresponse in patients receiving anti-tumor necrosis factor agents.

OBJECTIVES: The response rate of patients to hepatitis B virus (HBV) vaccination receiving anti-tumor necrosis factor (TNF) agents is quite low. We aimed to assess the efficiency of HBV vaccination in patients with chronic inflammatory diseases (CIDs) receiving anti-TNF agents as well as in healthy controls. We also evaluated the impact of different factors on the efficacy of HBV vaccination. METHODS: Patients with CIDs receiving anti-TNF agents and healthy controls vaccinated for HBV were included in the study during 2018-2019. An adequate immune response and an effective immune response to HBV were defined as >10 IU/L and > 100 IU/L, respectively. RESULTS: Among 274 participants, 187 were patients with CID and 87 were healthy controls. The mean age of the patients with CID (43.9 ± 11.7 years) was significantly higher than that of the healthy controls (31.4 ± 7 years) (P = 0.000). Adequate immune response was 60.8 and 94.3% in patients with CID and healthy controls (P = 0.000), respectively, whereas effective immune response was 37.9 and 75.9% (P = 0.000), respectively. In logistic regression analysis, male sex [odds ratio (OR), 0.408; 95% confidence interval (CI), 0.201-0.830; P = 0.013), use of infliximab (OR, 2.694; 95% CI, 1.203-6.035; P = 0.016) and sertoluzimab (OR, 3.307; 95% CI, 1.287-8.498; P = 0.013), vaccination after anti-TNF treatment (OR, 0.224; 95% CI, 0.083-0.602; P = 0.003) were identified as risk factors of nonresponse to HBV vaccine. CONCLUSIONS: Infliximab and sertoluzimab usage, male sex, and vaccination after anti-TNF treatment were risk factors of nonresponse. HBV vaccination should be given to patients with CID before initiation of anti-TNF treatment and awareness should be spread on this subject.

The Effect of Antiretroviral Therapy on IL-6, IL-1ß, TNF-α, IFN-γ Levels and their Relationship with HIV-RNA and CD4+ T Cells in HIV Patients.

BACKGROUND: Serum cytokine levels over the course of HIV infection usually increase with immunosuppression and decrease after antiretroviral treatment (ART). OBJECTIVES: The aim of the study is to compare cytokine levels between HIV-infected patients (HIP) and controls and investigate the relationship between CD4+T cell count, HIV-RNA levels, and cytokine levels. METHODS: The study subjects comprised ART-naive HIP (n=30) with no comorbidities and age-and sex-matched healthy controls. We measured levels of IL-6, IL-1ß, TNF-α, and IFN-γ in serum samples of HIP at the beginning and at month 6 of ART and in controls. RESULTS: The mean age of the study subjects was 38.7 ±10.3 years, with men making up 86.7% of the study subjects (n=26). IL-6, IL-1ß, and TNF-α levels were significantly higher in both ART-naive (p<0.001, p=0.002, p=0.001) and ART-experienced HIP (p<0.001) than controls. The IFN-γ level was lower in both ART-naive and ART-experienced HIP compared to controls (p=0.082 and p=0.002). There was a positive correlation between the CD4+T cell count and serum concentration of IFN- γ(r=0.320, p<0.05). While the serum IFN-γ concentration showed a negative correlation with the HIVRNA level(r=-0.412, p<0.001), the serum IL-1ß, IL-6, and TNF-α concentrations showed a positive correlation with the HIV-RNA level (r=0.349, p<0.001; r:0.54, p<0.001; r:0.438, p<0.00). CONCLUSION: Although serum concentrations of IL-6, IL-1ß and TNF-α showed a significant decrease after ART, they were still significantly higher than the controls. IFN-γ responded differently to ART compared to the other cytokines, indicating that it may play a distinct and important role in the pathogenesis of HIV infection.

The microbiology of necrotizing pancreatitis and its impact on in-hospital and 1-year all-cause mortality.

BACKGROUND/OBJECTIVES: The data regarding the microbial spectrum in necrotizing pancreatitis and its impact on mortality is limited. Therefore, in this study, we aimed to investigate the agents identified in cultures and their impact on in-hospital and 1-year all-cause mortality. METHODS: Patients with necrotizing pancreatitis were retrospectively included in the study. Based on culture results, patients were classified as either negative culture or positive culture necrotizing acute pancreatitis. The main outcomes of the study were the identification of agents isolated in patients with pancreatic necrosis and to assess in-hospital, 30-day and 1-year all-cause mortality according to culture results. RESULTS: In total, 109 patients of whom 33 had positive cultures were included in the study. Most positive cultures were polymicrobial (66%) with a marked gram-negative bacterial dominance (63%). Klebsiella spp. were the most common identified pathogens. The patients a with positive culture had worse outcomes in terms of in-hospital, 30-day and 1-year all-cause mortality compared to patients with sterile culture results (n = 9, 27.3% vs. n = 4, 5.3%, P < 0.01 for in-hospital mortality; n = 11, 33.3% vs. n = 5, 6.6%, P < 0.01 for 30-day mortality; and n = 14, 42.4% vs. n = 10, 13.2%, P < 0.01 for 1-year mortality). CONCLUSION: When a microorganism was identified in patients with necrotizing acute pancreatitis, it was mostly polymicrobial in etiology with a gram-negative bacterial dominance. In our cohort, Klebsiella spp. were the most common isolated organisms. Especially the patients with polymicrobial etiology showed a very poor outcome both in-hospital and in the long-term. Local hospital flora may have an impact on culture results.

Clostridium difficile infection: Is there a change in the underlying factors? Inflammatory bowel disease and Clostridium difficile.

BACKGROUND / AIMS: Clostridium difficile is a Gram-positive, strict anaerobe, spore-forming bacterium. It can cause self-limiting mild diarrhea, severe diarrhea, pseudomembranous colitis, and fatal fulminant colitis. We aimed to investigate the changes in epidemiology and incidence of C. difficile infection in our hospital database. PATIENTS AND METHODS: Episodes of C. difficile toxin were identified in hospital database, and data such as age, sex, community versus hospital acquisition, intensive care follow-up, current or previous treatments with antibiotics within the past 3 months, medication with proton pump inhibitors, or immunosuppressive therapies were collected. RESULTS: Toxin-positive 78 individuals constituted the patient group. In univariate analyses, independent risk factors for toxin positivity were community versus hospital acquisition [odds ratio (OR), 5.49; 95% confidence interval (CI), 2.52-11.95; P = 0.0001], presence of inflammatory bowel diseases (IBDs) (OR, 21.5; 95% CI, 8.65-53.44; P = 0.0001), proton pump inhibitors' use (OR, 4.53; 95% CI, 1.97-10.43; P = 0.0001), immunosuppressive drug use (OR, 4.1; 95% CI, 2.01-8.3; P = 0.0001), and use of quinolone group of antibiotics (OR, 5.95; 95% CI, 1.92-18.46; P = 0.001). Antibiotic use was a protective risk factor (OR, 0.09; 95% CI, 0.01-0.78; P = 0.01) and presence of IBDs was an independent risk factor (OR, 6.8; 95% CI, 1.5-30.08; P = 0.01) in community-acquired group (OR, 0.09; 95% CI, 0.01-0.78; P = 0.01). CONCLUSION: In recent studies, C. difficile infections were demonstrated to be more frequent in younger individuals who did not have a history of hospitalization but had an underlying disease such as IBD. In our study, we showed the change in the epidemiological data with prominence of underlying diseases such as IBDs.

Mortality markers in nosocomial Klebsiella pneumoniae bloodstream infection.

PURPOSE: Klebsiella pneumoniae is the most common endogen agent for nosocomial infections. In this study, mortality markers were investigated in patients with nosocomial K. pneumoniae blood stream infection (NKp BSI). METHODS: The characteristics of patients >16 years who had NKp BSI diagnosis by daily active surveillance between January 2012 and January 2016 were retrospectively evaluated. Patients who died until 28th day of the clinical follow up and those who survived until this time were statistically compared in terms of various risk factors. RESULTS: One hundred ninety patients were included into the study. Mortality rate was 47.9%, carbapenem resistance was 43.2%. Statistical analysis have shown that in presence of post-NKp BSI sepsis, septic shock, following in intensive care unit (ICU), meropenem resistance, kidney failure, NKp BSI secondary to pneumonia, use of invasive instruments such as central venous catheter (CVC), urinary catheter (UC) and mechanical ventilator (MV), colostomy, transfusion and hemodialysis mortality was significantly higher. In patients admitted into the hospital for neurological disorders, pancreaticobiliary tract (PBT) diseases and patients who have undergone endoscopic retrograde cholangiopancreatography (ERCP) and patients in whom NKp BSI secondary to PBT infection mortality rate was lower. CONCLUSIONS: Sepsis, septic shock, clinical conditions requiring ICU treatment and meropenem resistance increase mortality rates in NKp BSI significantly. Mortality was higher also in patients with NKp BSI secondary to pneumonia, in kidney failure and when invasive instruments were used. On the other hand, in patients who were admitted to the hospital for neurological disorders and PBT diseases mortality rate was lower.