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.

Epidemiological and Clinical Features of Salmonella Typhi Infection Among Adult Patients in Qatar: A Hospital-based Study.

OBJECTIVES: We sought to describe the epidemiological and clinical features of typhoid fever in Qatar. METHODS: We conducted a retrospective study of adult patients treated for typhoid fever at Hamad General Hospital and Alkhor Hospital between 2005 and 2012. RESULTS: The mean age of the 354 patients enrolled in the study was 28.4±9.3 years; 296 (83.6%) were males. There were 42, 48, 39, 44, 46, 47, 52, and 36 cases of adults with typhoid fever in 2005, 2006, 2007, 2008, 2009, 2010, 2011, and 2012, respectively. Overall, 343 (96.9%) patients had a history of travel to endemic areas. Among them, 93.0% acquired typhoid fever in the Indian subcontinent. Fever was observed in all cases, and the other predominant symptoms were abdominal pain (38.1%), diarrhea (35.6%), and headache (33.1%). Salmonella typhi, showed high resistance to ciprofloxacin (n = 163; 46.0%), and low resistance to ceftriaxone (n = 2; 0.6%). Four patients developed intestinal perforation, which was surgically repaired in two cases. Two patients (0.6%) died. CONCLUSIONS: Typhoid fever was frequent among immigrants to endemic areas. Travelers returning from endemic areas with suspected typhoid fever should be treated empirically with third-generation cephalosporin after obtaining appropriate cultures. Moreover, preventive measurements such as education on food and water hygiene, and effective vaccination of travelers should be practiced widely among travelers to endemic areas to reduce morbidity and mortality.

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.

Adult tuberculous meningitis in Qatar: a descriptive retrospective study from its referral center.

BACKGROUND: Tuberculous meningitis is the severest and commonest form of central nervous system tuberculosis causing high mortality and morbidity. We aim to study the clinical, biochemical, and radiological characteristics of tuberculous meningitis in adult patients in Qatar and to calculate the incidence. METHODS: A descriptive retrospective 7-year study was conducted at the Hamad General Hospital (the only tertiary referral center and sole health care provider for tuberculosis in Qatar) between the 1st of January 2006 and the 31st of December 2012, to describe the clinical presentation, diagnosis, treatment, outcome, and the incidence of adult tuberculous meningitis in Qatar. RESULTS: Tuberculous meningitis was diagnosed in 80 patients (65 male, 15 female), with a mean age of 30.3 ± 8.9. The majority of patients (76.3%) were from the Indian subcontinent. The commonest clinical features were fever (79%), headache (71%), and meningism (56%). Cerebrospinal fluid tuberculosis culture was positive in 44% of patients. Almost 39% of patients were in Stage I, 46% in Stage II and 15% in Stage III of the disease. The commonest neuroimaging features were leptomeningeal enhancement (34%) and hydrocephalus (33%). Cranial nerve palsy, limb weakness, and an elevated C-reactive protein were associated with a poorer outcome. Sixty eight percent had complete recovery, 10% had residual neurological sequelae without disability, 17% had disability, and 5% died. The average incidence of tuberculous meningitis over 7 years was 0.9 per 100,000 adult population. CONCLUSION: The characteristics of tuberculous meningitis were described in our population. Our data indicate that the incidence of tuberculosis meningitis in Qatar has increased. Tuberculous meningitis in Qatar is mainly an imported disease.

Strongyloides stercoralis hyperinfection after corticosteroid therapy: a report of two cases.

Two cases of Strongyloides stercoralis hyperinfection are described. Both patients were expatriates from the Indian subcontinent, and reported the use of corticosteroids. The first patient presented with severe pulmonary disease that necessitated respiratory support, followed by acute abdomen and intestinal obstruction and he succumbed to these diseases. The second patient also presented with acute pulmonary disease, which responded to antihelmintic treatment and supportive care; however, he died later due to his primary disease. The clinical features of S stercoralis hyperinfection are nonspecific; therefore, a high index of suspicion is required for early diagnosis and to start appropriate therapy. Because of the seriousness of the disease and the associated high mortality we suggest screening for S stercoralis in patients from endemic areas who will be taking immunosuppressive therapy.