Epidemiological characteristics of de novo hepatitis B infection in liver transplant recipients-An experience from a tertiary care centre in Qatar.

BACKGROUND: The emergence of hepatitis B surface antigen in a patient with previously negative hepatitis B virus (HBV) serology post-orthotropic liver transplant (OTLX) is known as de novo hepatitis B (DNHB). As there are no data on patients with DNHB available from Qatar, we aim to do a pioneer study indexing their clinical profile and epidemiology of patients with DNHB in Qatar. MATERIALS AND METHODS: This descriptive epidemiological study was done by retrospectively reviewing records of 159 post-OTLX patients. HBV serology of these patients post-OTLX was reviewed, and 17 were identified as DNHB cases. Baseline epidemiological characteristics were defined and compared between DNHB cases and the rest. DNHB cases were analyzed statistically using the chi-square test and Kaplan-Meier curve. RESULTS: The majority of the subjects were men (65%) and Qataris (40%). Mean age was 57.4 ± 12.5 years. Bulk of them underwent OTLX in China (44%). The overall incidence of DNHB was 10.7%, with transplants in China having significantly higher incidence than transplants from all other countries. The mortality rate was 23.5% in DNHB cases compared to 2.8% in non-DNHB. 67% of patients survived at least 64 months after the diagnosis of DNHB. Five-year survival did not vary significantly between those with DNHB and those without. CONCLUSION: Orthotropic liver transplant in centers selecting donors liberally without screening for HBV poses the risk of DNHB. We recommend having protective levels of HBs antibodies before OTLX. Prophylactic antiviral treatment should be considered until peri-operative HBV transmission has been excluded by screening hepatic tissue for HBV DNA.

Diagnostic difficulties in human rabies: A case report and review of the literature.

Rabies is a zoonotic disease with the highest fatality rate of any infectious disease. The clinical features of rabies encephalopathy are highly nonspecific at the onset and clinicians from low endemic areas usually face difficulties in recognizing cases during the early stages. The need for establishing a rapid and accurate test to identify rabies during the ante-mortem period is important. However, in actual clinical practice, the latter may remain difficult for various reasons. In human rabies, positively identifying the antigen, antibody or genetic material by various diagnostic methods during the symptomatic period is affected by the unpredictable nature of viremia, levels of antibody immune response of the host, and the virulence of the infecting strain. Also, more advanced testing with greater sensitivity may not be readily available at all centers. Here we describe a case of a young male who was bitten by a rabid dog and developed progressive encephalopathy with a fatal outcome, with negative antibodies in the cerebrospinal fluid (CSF). A review of the literature on the clinical features, diagnostic tests, treatment and prevention of rabies is also presented.

Clinical and Epidemiological Characteristics of Stenotrophomonas maltophilia Associated Lower Respiratory Tract Infections in Qatar: A Retrospective Study.

Background Stenotrophomonas maltophilia is a rapidly emerging nosocomial pathogen with intrinsic or acquired resistance mechanisms to several antibiotic classes. It can cause life-threatening opportunistic pneumonia, particularly among hospitalized patients. Incidence of infections by S. maltophilia has been reported as 0.07-0.4% of hospital discharges, but its mortality is 20 -60%. This is the first study from Qatar indexing the clinical and epidemiological characteristics and antibiotic susceptibility of S. maltophilia. Materials and methods This retrospective descriptive epidemiological study was conducted in 6 tertiary care hospitals under Hamad Medical Corporation in Doha, Qatar, analyzing inpatient respiratory isolates of S. maltophilia during 2016-17. Out-patients, children below 14 years, and non-respiratory samples except blood cultures in patients with pneumonia were excluded. Clinical records were reviewed to identify possible risk factors. Infection and colonization were identified using the Centers for Disease Control and Prevention (CDC) algorithm for clinically defined pneumonia and statistically analyzed using the chi-square test and Pearson's correlation. Results S. maltophilia was isolated from 2.07% (317/15312) of all respiratory samples received in the microbiology lab during our study period. Three hundred seventeen patients studied had a mean age of 60 ± 20 years, and 68% were men. Most of the isolates were from sputum (179), followed by tracheal aspirate (82) and bronchoscopy (42). Fourteen blood culture samples from patients diagnosed with pneumonia were also included. 67% were hospitalized for more than two weeks, 39.1% were on mechanical ventilators, and 88% had received a broad-spectrum antibiotic before the event. 29.1% were deemed to have an infection and 70.9% colonization. Incidence of infection in those with Charlson's Co-morbidity Index (CCI) ≥ 3 was 36.5% compared to 24.2% in those with CCI < 3 (Relative Risk (RR)=1.52; 95% CI: 1.04,2.18; p=0.01). Patients with recent chemotherapy, immunosuppressant, or steroid use had a significantly higher infection risk than those without (69.2% v/s 23.3% RR=2.96; 95% CI:2.2,3.9; p<0.005). The most common symptoms in patients with infection were fever (96%) and expectoration (61.9%). The most common radiological finding was lobar consolidation (71.6%). Mean CRP and procalcitonin were 106.5±15.5 mg/l and 12.3 ± 14 ng/ml. Overall mortality was 16.3%. Patients on mechanical ventilator with IBMP-10 score ≥ 2 had 22.8% mortality compared to 5.7% in those with score < 2 (RR=3.9;95%CI:0.9,16.6; p<0.015). As per The US Clinical and Laboratory Standards Institute (CSLI) breakpoint values, Trimethoprim-Sulfamethoxazole (TMP-SMX) showed the highest sensitivity (97.8%), followed by levofloxacin (71.6%). 0.3% of samples were pan-drug resistant. Conclusions S. maltophilia is a frequent nosocomial colonizer, but it can cause nosocomial pneumonia in almost one-third of cases, specifically in immunocompromised and patients with CCI ≥ 3 with a high risk of mortality due to ventilator-associated pneumonia (VAP) in those with IBMP-10 ≥ 2. Prolonged hospital stay is a risk factor for colonization by S. maltophilia, while recent chemotherapy, immunosuppressant, or steroid use are risk factors for hospital-acquired pneumonia due to S. maltophilia. TMP-SMX and levofloxacin are the only reliable agents for monotherapy of respiratory infections due to S. maltophilia in Qatar.

Tuberculosis in an Allogeneic Transplant Kidney: A Rare Case Report and Review of Literature.

Tuberculosis (TB) is a common post-transplant infection with high prevalence in developing countries due to reactivation. Post-transplant TB involves the respiratory system in 50% of patients, followed by disseminated involvement in 30%. The risk of tuberculosis of renal allograft post-transplantation is determined by disease endemicity in the donor population and the immunosuppressant regimen. TB can cause allograft rejection and graft loss due to delayed diagnosis or reduced immunosuppressant drug efficacy. A 23-year-old lady was seen 40 days after cadaveric unrelated renal transplantation from China. She was on immunosuppression with tacrolimus, mycophenolate, and prednisolone. Examination showed low-grade fever and infected surgical site in the right iliac fossa draining pus. Imaging showed fluid pockets, parenchymal micro-abscesses, and perinephric collections in the right iliac fossa communicating with skin. A diagnosis of renal allograft TB without dissemination was made after TB polymerase chain reaction (PCR) from early morning urine was positive. She was started on anti-TB therapy. The sinus tract healed, and renal parameters improved after six months of therapy. Follow-up magnetic resonance imaging (MRI) showed resolution of the micro-abscesses as well as the surrounding fluid collection. Renal angiogram demonstrated well-perfused, normally functioning, non-obstructed renal transplant. Tuberculosis of renal allograft should be considered in a transplant recipient with pyrexia of unknown origin and persistent discharge from the surgical site, not responding to antimicrobials. Tuberculosis of transplant kidney can cause graft loss due to allograft rejection when there is a delayed diagnosis, or as anti-TB drugs reduce the efficacy of immunosuppressant medications. The index of suspicion should be high when donor status is unknown or if the donor is from an endemic tuberculosis area. Timely diagnosis and treatment helped to save the transplanted kidney of our patient without rejection.