Widal agglutination test - 100 years later: still plagued by controversy.

We review the significance of the Widal agglutination test in the diagnosis of typhoid fever. Over 100 years since its introduction as a serologic means of detecting the presence of typhoid fever, the Widal test continues to be plagued with controversies involving the quality of the antigens used and interpretation of the result, particularly in endemic areas. Areas of concern with clinical and laboratory significance discussed in this review include: the techniques of test performance, interpretation of results, limitation of the value of the test results in endemic typhoid areas, the quality of the antigens used, and alternative diagnostic tests.

Intravenous immunoglobulin in symptomatic and asymptomatic children with perinatal HIV infection.

One hundred thirty-five children born to human immunodeficiency virus (HIV)-infected mothers were selected randomly to receive immunoglobulin (Gamimune-N, Miles Pharmaceutical Co) 200 mg/kg monthly for 1 year. All patients were seropositive by ELISA and Western blot at birth. At the time of the study, 15 symptomatic (P2) and 57 asymptomatic (P1) patients with evidence of viral infection (positive HIV culture or P24 antigen) received the immunoglobulin. Sixty-three indeterminate (PO) patients with no evidence of infection served as the control. Mean age for infants in group P2 was 32 months, 26 months for group P1, and 11 months for group PO. Significant reduction in the frequency of bacterial infections (ie, otitis media, upper respiratory tract infections, urinary tract infections, and acute gastroenteritis) was seen in the symptomatic group compared with both the asymptomatic and the control groups. Growth as measured by weight and height > 50th percentile was also markedly better in the symptomatic group than either asymptomatic or control patients. There was no significant difference in head circumference in all three groups. These results indicate that monthly intravenous immunoglobulin infusion (IVIG) appears to be beneficial to both symptomatic and asymptomatic HIV patients in reducing the frequency of bacterial infection and also enhancement of the immune response. However, symptomatic patients responded much better than the asymptomatic patients.

Parasitic infections in sickle cell crisis: Nigerian experience.

Data collected on 150 sickle cell patients in Nigeria were analyzed to determine the frequency of parasitic infections in clinical and hematologic crisis. Fifty-three adult and 97 pediatric patients (mean age: 27.6 years and 9.7 years, respectively) were studied. Of these patients, 82 were males and 68 females. One hundred thirty-nine had the SS and 11 the SC genotype. Blood samples collected from patients on admission for sickle cell-related illnesses were examined microscopically for evidence of Plasmodium sp, and stool samples were analyzed for presence of any helminth. A total of 102 parasitic infections associated with clinical cases of sickle cell crisis were recorded (malaria, 36[35.3%]; helminths, 49 ([48%]; and malaria and helminths together, 17 [16.7%]). Of the 49 helminthic infections, 26 (53.1%) were due to Ascaris lumbricoides, 15 (30.6%) were due to hookworms, 7 (14.3%) were due to Trichuris trichiura, and 1 (2%) was due to Strongyloides stercoralis. The mean hemoglobin levels during clinical crisis were 7.1 g/dL for helminths, 6.4 g/dL for malaria, and 6.1 g/dL for malaria and helminths together. Reticulocyte counts were 1.4% for helminths, 1.5% for malaria, and 1.2% for both malaria and helminths together. Severity and duration of the clinical crisis were longer for events associated with a single parasitic organism infection than for those with multiple organisms. Routine blood smear examination for malaria and stool analysis should be included in the laboratory evaluation of individuals with sickle cell anemia in developing countries as these infestations could play an important role in precipitating a crisis.

Eikenella corrodens endocarditis in an intravenous drug user: case report and literature review.

A rare case of Eikenella corrodens endocarditis in an intravenous drug user is reported. Repeated blood cultures from the patient established the diagnosis of this infection. However, evaluation of the cardiac function using two-dimensional echocardiography with Doppler flow demonstrated a large pedunculated tricuspid vegetation. Also evident on this study was a dilated right ventricle with diminished contractility and regurgitation. Complete sterilization of the blood was achieved after a 2-week course of intravenous penicillin and gentamicin followed by an additional 4-week course of intravenous penicillin alone. Clinicians treating suspected IV drug users should be aware of the potential pathogenicity of this rare, facultative, anaerobic gram-negative bacillus (E corrodens). A combination of intravenous penicillin and aminoglycoside should be considered as the initial treatment followed by an additional course of intravenous penicillin for such patients with valvular vegetation.

Autopsy findings in HIV-infected inner-city patients.

To assess the importance of the autopsy in HIV-1 infection, we retrospectively reviewed the autopsy reports of 70 HIV-1-seropositive patients at Howard University Hospital. Of the 58 patients with AIDS, the diagnosis of AIDS was made after autopsy in 24 (41%) cases. The lung was the most common site of AIDS-diagnostic diseases, and was affected in 90% of patients. Pneumocystis carinii infection was the most common AIDS-diagnostic disease, and was present in 50% of the AIDS patients. Thirty-eight percent of AIDS diagnostic diseases were diagnosed antemortem, including 15 of the 29 Pneumocystis carinii infections. Most of the AIDS-diagnostic diseases were disseminated at autopsy and two or more diseases were found in some organs. Overall, Pneumocystis carinii pneumonia was the most common cause of death, accounting for a mortality of 43% among AIDS patients. Bacterial infections were common and contributed to the mortality and morbidity of both AIDS and non-AIDS patients. Bacterial infection was the cause of death in 15 AIDS and 9 non-AIDS patients. The clinical cause of death concurred with the pathological cause in 53% of our cases.

Clinical apnea as an early manifestation of Pneumocystis carinii pneumonia in an infant with perinatal HIV-1 infection.

This article describes the first case of Pneumocystis carinii pneumonia in a human immunodeficiency virus (HIV) seropositive infant in whom apnea was the earliest presenting clinical finding. Pediatricians treating infants with HIV infection need to be aware of this unusual clinical presentation of P carinii pneumonia to avoid a delay in diagnosis and management of this disease.

Pneumococcal sepsis and meningitis in adults with sickle cell disease.

Patients with sickle cell disease are predisposed to infection caused by Streptococcus pneumoniae. However, there has been only one published case of bacteremic pneumococcal meningitis in an adult with sickle cell anemia. We report here the cases of six adults with sickle cell disease, pneumococcal sepsis, and meningitis. Five patients were male and one was female. Their ages ranged from 18 to 34 years (mean, 25.7 years). Five patients had the SS and one had the SC hemoglobin phenotype. Only one patient had received pneumococcal vaccine (14 valent). This vaccine did not protect against the pneumococcal serotype causing his infection. All patients had high fever (mean, 39.8 degrees C [103.7 degrees F]) on admission; five had generalized weakness and four had neck stiffness. Leukocyte counts were greater than 30,000/mm3 in all patients. Streptococcus pneumoniae was isolated from the blood and the cerebrospinal fluid in all patients. The cerebrospinal fluid showed pleocytosis in six patients, an elevated protein level in five, and hypoglycorrhachia in two. Complications included renal failure in four patients, disseminated intravascular coagulation in one, and seizures in another. Two patients died. Pneumococcal sepsis and meningitis are uncommon in adults with sickle cell disease, but they carry a high morbidity and mortality. Wider use of the new 23-valent polysaccharide vaccine in these patients is recommended.