Toxoplasma gondii antibodies in HIV and non-HIV infected Thai pregnant women

Serological evidence for Toxoplasma gondii infection in Thai pregnant women was investigated. One thousand six hundred and sixty-nine blood specimens were collected from 838 HIV-seropositive and 831 HIV-seronegative pregnant women attending the antenatal-care clinic at Siriraj Hospital, Bangkok, Thailand, during a two-year period. Toxoplasma IgG antibody was detected, using a solid-phase enzyme-linked immunosorbent assay in which the membrane protein p-30 was the predominant antigen. IgG positive sera were subsequently examined for IgM antibody by the capture antibody enzyme immunoassay. The IgG antibody was found in 450 (53.7%) HIV seropositive women and 44 (5.3%) non-HIV infected women, with a statistically significant difference (p < 0.0001). Three of the 450 HIV-seropositive and 2 of the 44 HIV-seronegative sera with IgG antibody were positive for IgM antibody against T. gondii. This result suggested that HIV seropositive pregnant women had a higher risk of Toxoplasma infection with increase exposure to their offspring.     

Immune Activation and Viral Replication after Vaccination with an Influenza A H1N1 2009 Vaccine in HIV-Infected Children Receiving Antiretroviral Therapy

Immunization with a pandemic influenza A H1N1 2009 was recommended for HIV-infected patients. However, there is limited information concerning the impact of immunization with this vaccine on immune activation and HIV viral replication. In this study, 45 HIV-infected children and adolescents receiving antiretroviral therapy were immunized with a 2-dose series of nonadjuvated monovalent influenza A H1N1 2009 vaccine upon enrollment and approximately 1 month later. Immunogenicity was determined by haemagglutination inhibition assay. The level of immune activation was determined by identification of CD38 and HLA-DR on CD8+ T cells. Patients were divided into 2 groups which include patients who had an undetectable HIV viral load (HIV detectable group) and patients who show virological failure (HIV nondetectable group). The results showed seroconversion rate of 55.2% in HIV nondetectable group, whereas 31.3% was found in HIV detectable group. Both groups of patients showed no major increase in immune activation after immunization. Interestingly, a decrease in the frequency of CD8+ T cells that coexpressed CD38 and HLA-DR was observed after immunization in both groups of patients. We suggested that immunization with influenza A H1N1 2009 vaccine can induce immune response to the pandemic virus without major impact on HIV viral replication and immune activation.     

Hemophagocytic lymphohistiocytosis following dengue hemorrhagic fever in Hb H/Hb Constant Spring patient

Infection‐associated hemophagocytic syndrome (IAHS), a secondary form of hemophagocytic lymphohistiocytosis (HLH), has been found following several types of infections and can be fatal. We report herein a case of IAHS following dengue infection in a 14‐year‐old patient with underlying α‐thalassemia syndrome (non‐deletional Hb H/Hb Constant Spring disease). He developed prolonged fever, thrombocytopenia, and progressive splenomegaly. Further investigations indicated hyperferritinemia, and increased reactive histiocytes with hemophagocytic activity in the bone marrow. He responded promptly to dexamethasone and i.v. immune globulin. Physicians should be aware of this condition, especially in countries where both dengue hemorrhagic fever and thalassemia are prevalent. The fatal outcome of IAHS can be prevented with prompt appropriate treatment.     

Intestinal parasitic infections among human immunodeficiency virus-infected and -uninfected children hospitalized with diarrhea in Bangkok,Thailand

A prospective observational study was conducted to determine the prevalence and the clinical impact of intestinal parasitic infections in diarrheal illness among HIV-infected and HIV-uninfected children hospitalized with diarrhea in Bangkok, Thailand. Stool samples were examined for intestinal parasites using a simple smear method, a formalin-ether concentration method, a modified acid-fast stain and a modified trichrome stain. Intestinal parasites (IP) were identified in the stool specimens of 27 of 82 (33%) HIV-infected and 12 of 80 (15%) HIV-uninfected children (p=0.01). Microsporidia and Cryptosporidium were the most common IP found. Eighty-two percent of HIV-infected and 97% of HIV-uninfected groups presented with acute diarrhea and 76% of each group had watery diarrhea. Pneumonia was the most common concurrent illness, found in 22%. Clinical findings were unable to differentiate children infected with IP. Sixty-three percent of HIV-infected and 83% of HIV-uninfected children who had IP made a satisfactory recovery without specific anti-parasitic therapy. However, 9 children (7 HIV-infected and 2 HIV-uninfected) with persistent diarrhea who also had cryptosporidiosis and/or microsporidiosis did not respond to azithromycin and/or albendazole respectively. HIV-infected children with cryptosporidiosis were older and had more advanced HIV infection than those with microsporidiosis. Routine stool examination for IP should be considered due to the absence of clinical markers. The lack of effective therapy for the major IP found underscores the importance of preventive measures.     

A child with avian influenza A (H5N1) infection

Human infections with avian influenza viruses can be severe and may be harbingers of the evolution of a pandemic strain. We present a patient in Thailand who was infected with influenza A (H5N1) virus. Prominent features included the progression from fever and dyspnea to the acute respiratory distress syndrome in a short period, lymphopenia and thrombocytopenia. Establishing the diagnosis for this patient increased public awareness of the virus and was soon followed by a halting of poultry-to-human transmission. On the basis of available data, any child with suspected avian influenza infection should be treated with oseltamivir.