Effectiveness and safety of protease inhibitor-based regimens in HIV-infected Thai children failing first-line treatment.

OBJECTIVES: Virological failure on first-line nonnucleoside reverse transcriptase inhibitor (NNRTI)-based treatment regimens has become a problem in HIV-infected children on long-term antiretroviral therapy (ART). Protease inhibitor (PI)-based regimens are therefore often given to children failing NNRTI-based regimens. The aim of the study was to assess the 48-week effectiveness, safety and predictive factors for viral suppression of PI-based regimens in HIV-infected Thai children who had failed NNRTI-based regimens. METHODS: This study assessed 41 HIV-infected children who had failed first-line NNRTI-based regimens and were switched to PI-based regimens for at least 48 weeks. We assessed their CD4 cell counts, plasma HIV RNA levels, weight-for-age and height-for-age z-scores, and adverse events. RESULTS: The children's median age was 9.5 years (range 1.5-15.8 years). At baseline, their median CD4 cell count was 276 cells/µL [interquartile range (IQR) 160-749 cells/µL], and their median plasma HIV RNA level was 4.5 log10 HIV-1 RNA copies/mL (IQR 3.9-4.8 log10 copies/mL). After 48 weeks of PI-based therapy, their CD4 cell counts increased to a median of 572 cells/µL (IQR 343-845 cells/µL) and in 73.2% plasma HIV RNA levels decreased to < 50 copies/mL. Their median weight-for-age and height-for-age z-scores were stable over the period of the study. Diarrhoea occurred in 29.3% of patients. Triglyceride levels were significantly higher at weeks 24 and 48 in comparison to baseline measurements. CONCLUSIONS: PI-based regimens are safe and effective for HIV-infected Thai children who have failed first-line NNRTI-based regimens. However, long-term follow-up is warranted in order to ascertain the feasibility and sustainability of these new regimens.

Causes of first hospitalization among 1121 HIV-infected children: comparison of the pre-Pneumocystis jiroveci pneumonia prophylaxis, pre-antiretroviral therapy and antiretroviral therapy periods.

This study identified causes of first hospitalization among perinatally acquired HIV-infected children at Chiang Mai University Hospital between 1989 and 2009. Data were stratified into three seven-year time periods: pre-Pneumocystis jiroveci pneumonia (PJP) prophylaxis, pre-antiretroviral therapy (ART) and ART period. Over the 21-year study period, 1121 children were hospitalized. The mean age at admission was 2.7 years and had become older over time. Of the 1121 hospitalization causes, 50.6% were AIDS-defining illnesses (ADIs), 48.1% were non-AIDS-defining illnesses (NADIs) and 1.3% were related to immune reconstitution syndrome. Types of ADIs changed over time: PJP and recurrent Salmonella septicaemia decreased, while mycobacterial infection and systemic fungal infection increased. For NADIs, bacterial infections, viral infections and gastrointestinal problems decreased, but haematological problems increased in the third period. Decline in the number of hospitalizations and mortality rate, increase in the mean age of hospitalized children, change in the distribution of specific illnesses and appearance of immune reconstitution syndrome were observed in the ART period.

Fulminant enterovirus 71 infection: case report.

A previously healthy 3-year-old boy presented with high-grade fever, dyspnoea, alteration of consciousness, tachycardia and shock. A few erythematous macules and papules were seen on his palms and soles. Echocardiogram showed poor left ventricular contraction. Cardiac enzymes and pro-B-type natriuretic peptide were elevated. Milrinone, low-dose dopamine and intravenous immunoglobulin were administered. The patient recovered after 5 days without cardiac or neurological sequelae. The serological results showed a four-fold rise of enterovirus 71. In children with severe EV71 infection, early recognition of cardiopulmonary involvement and aggressive treatment are crucial to successful management.

HIV-1 drug resistance mutations in children after failure of first-line nonnucleoside reverse transcriptase inhibitor-based antiretroviral therapy.

OBJECTIVES: The aim of the study was to assess the prevalence, predictors and patterns of genotypic resistance mutations in children after failure of World Health Organization-recommended initial nonnucleoside reverse transcriptase inhibitor (NNRTI)-based treatment regimens. METHODS: We carried out a multicentre retrospective study of genotyping tests performed for all HIV-infected children at eight paediatric centres in Thailand who experienced failure of NNRTI therapy at a time when virological monitoring was not routinely available. RESULTS: One hundred and twenty children were included in the study. Their median age (interquartile range) was 9.1 (6.8-11.0) years, the median duration of their NNRTI regimens was 23.7 (15.7-32.6) months, their median CD4 percentage was 12% (4-20%), and their median plasma HIV RNA at the time of genotype testing was 4.8 (4.3-5.2) log(10) HIV-1 RNA copies/mL. The nucleoside reverse transcriptase inhibitor (NRTI) resistance mutations found were as follows: 85% of the children had M184V/I, 23% had at least four thymidine analogue mutations, 12% had the Q151M complex, 5% had K65R, and 1% had the 69 insertion. Ninety-eight per cent of the children had at least one NNRTI resistance mutation, and 48% had etravirine mutation-weighted scores ≥4. CD4 percentage <15% prior to switching regimens [odds ratio (OR) 5.49; 95% confidence interval (CI) 2.02-14.93] and plasma HIV RNA>5 log(10) copies/mL (OR 2.46; 95% CI 1.04-5.82) were independent predictors of at least four thymidine analogue mutations, the Q151M complex or the 69 insertion. CONCLUSIONS: In settings without routine viral load monitoring, second-line antiretroviral therapy regimens should be designed assuming that clinical or immunological failure is associated with high rates of multi-NRTI resistance and NNRTI resistance, including resistance to etravirine.

Low prevalence of insulin resistance among HIV-infected children receiving nonnucleoside reverse transcriptase inhibitor-based highly active antiretroviral therapy in Thailand.

BACKGROUND: Highly active antiretroviral therapy (HAART) is reported to cause insulin resistance among adults, but effects on children are less clear. We attempted to describe the prevalence of insulin resistance among HIV-infected children receiving HAART. METHODS: Insulin resistance was assessed at 96 weeks of treatment with nonnucleoside reverse transcriptase inhibitor (NNRTI)-based HAART (nevirapine or efavirenz with stavudine and lamivudine) among children in Chiang Mai, Thailand. Insulin resistance was defined as homeostasis model assessment for insulin resistance (HOMA-IR) >/=3.16, fasting c-peptide >/=4.40 ng/mL or fasting insulin >/=25.0 muU/mL. Impaired fasting glucose (IFG) was defined as glucose >/=110 mg/dL. Measurements were analysed for associations with age, lipodystrophy, treatment regimen and clinical data. RESULTS: The prevalence of insulin resistance was 6.5%; no child had IFG. Those with insulin resistance were older with higher body mass index. Children >/=10 years had higher HOMA-IR, c-peptide and insulin, but no difference was seen in the frequency of insulin resistance. No associations between insulin resistance and lipodystrophy or treatment regimen were detected. CONCLUSIONS: Insulin resistance is uncommon among children receiving NNRTI-based HAART and is unrelated to lipodystrophy.

Haematological changes after switching from stavudine to zidovudine in HIV-infected children receiving highly active antiretroviral therapy.

OBJECTIVE: In resource-limited countries, stavudine (d4T) is commonly used as part of the initial highly active antiretroviral therapy (HAART) regimen. Many patients who subsequently develop lipodystrophy switch from d4T to zidovudine (ZDV), a drug that can be myelotoxic. We aimed to study the spectrum and severity of haematological changes following this substitution. METHODS: This was a retrospective cohort study. The inclusion criteria were as follows: HIV-infected children were included who (1) were 2-15 years old at the time of HAART initiation, (2) had not been diagnosed as having haematological diseases, (3) had been receiving a first HAART regimen consisting of either nevirapine or efavirenz, together with lamivudine and d4T, for at least 48 weeks and (4) had switched from d4T to ZDV at least 48 weeks previously. RESULTS: Seventy-eight children were included in the study. Thirty-six (46%) were male. The mean age was 10.3 years (standard deviation 3.1 years). The switch had been made a median time of 65 weeks (range 48-97 weeks) previously. There was no significant change in CD4 lymphocyte count or percentage, or HIV RNA level, after the switch. There was a statistically significant decrease in haemoglobin level (12.6 vs.12.1 g/dL; P<0.001), total white blood cell (WBC) count (8088 vs. 6910 cells/microL; P<0.001) and absolute neutrophil count (ANC) (4320 vs. 3448 cells/microL; P<0.001). However, the decreases never reached Division of AIDS grade 3 or 4 severity, and none of the patients had clinical symptoms or signs of anaemia, leukopenia, or neutropenia. No participant had to discontinue ZDV during the 48-week follow-up period. CONCLUSION: In a paediatric population, statistically significant decreases in haemoglobin level, WBC count and ANC occurred following the substitution of d4T with ZDV, but the magnitudes of the decreases were small and not clinically significant.

Prevalence of protective antibody against measles in HIV-infected children with immune recovery after highly active antiretroviral therapy.

OBJECTIVES: This study was conducted to determine the prevalence of measles-protective antibody in HIV-infected children with immune recovery after highly active antiretroviral therapy (HAART). METHODS: Ninety-six HIV-infected children were enrolled in the study. Their mean age was 9.7+/-2.6 years, 47% were boys, and 47% were in Centers for Disease Control and Prevention (CDC) clinical category C. All participants had been treated with HAART until they achieved a CD4 cell percentage > or =15%. Three children with a history of clinical measles infection were not included in the data analysis. RESULTS: Only 39 out of 93 children (42%) had a measles-protective antibody level, defined as an anti-measles immunoglobulin G (IgG) level > or =320 mIU/mL. There was no significant difference between the groups with and without protective levels of measles antibody in gender, clinical category, age at which HAART was started, duration of severe immune suppression, CD4 cell count and percentage, or plasma HIV RNA level before and after HAART. CONCLUSIONS: We conclude that, despite a history of measles immunization and evidence of immune reconstitution after HAART, many healthy HIV-infected children are still susceptible to measles.

Penicillium marneffei mesenteric lymphadenitis in human immunodeficiency virus-infected children.

UNLABELLED: Disseminated P. marneffei infection is one of the common opportunistic infections seen in HIV-infected patients in Southeast Asia. We report 3 cases of HIV-infected children with mesenteric lymphadenitis presented with prolonged fever and abdominal pain. The first two patients were diagnosed as peritonitis and acute appendicitis prior to exploratory laparotomy. Operative findings revealed multiple enlarged mesenteric lymph nodes. Histopathologic findings of mesenteric lymph nodes biopsy were characteristic for P. marneffei infection. Mesenteric lymphadenitis in the last patient was diagnosed by abdominal ultrasound. All three cases had positive blood and bone marrow cultures for P. marneffei. These patients were treated with amphotericin B. Fever declined in 3-6 days. The first two patients survived but the last one subsequently died from underlying hemophilia A (GI bleeding). CONCLUSION: Acute mesenteric lymphadenitis can be one of the unusual manifestations caused by P. marneffei. Southeast Asia is an endemic area for P. marneffei and is severely affected by acquired immunodeficiency syndrome epidemic. Therefore, mesenteric lymphadenitis should be considered in HIV-infected persons who present with prolonged fever and abdominal pain.

Immunohistochemical characterization of a new monoclonal antibody reactive with dengue virus-infected cells in frozen tissue using immunoperoxidase technique.

This paper presents a novel monoclonal antibody shown to react with cytoplasmic antigens in various dengue infected human frozen organs from autopsy and necropsy specimens. Strong reactivity was found in hematopoietic cells, including immunoblasts, lymphocytes, plasma cells and macrophages of spleen, lymph node, lung, kidney and stomach. Strikingly, strong positivity was demonstrated in cerebral cortex neurones, Purkinje cells, choroid plexus and blood vessels in addition to astrocytes and microglia. Neurotropism of the virus could explain the meningitis, encephalitis, mononeuropathy and polyneuropathy observed by direct toxicity, but noted especially after an activation of mononuclear phagocytes and amplification of the immune response with subsequent vascular inflammation and formation of immune complexes.

Primary sequence of the envelope glycoprotein of a dengue type 2 virus isolated from patient with dengue hemorrhagic fever and encephalopathy.

Dengue viruses exist in nature as a collection of highly similar but not identical members (quasispecies). In order to correlate the presence of viral quasispecies with rare occurrence of unusual clinical manifestations in dengue-infected individuals, a dengue type 2 virus was isolated from the peripheral blood of a 12-year-old boy who presented with fever, headache, drowsiness and tonic seizure of the left arm, and subsequently manifested symptoms and signs of dengue hemorrhagic fever. Analysis of the envelope glycoprotein sequence of the encephalopathy-associated virus and two other dengue type 2 viruses from the same epidemic season in Chiang Mai, Thailand revealed that all three viruses belonged to the subtype IIIa of the five-subtype phylogenetic nomenclature system for dengue type 2 virus. The encephalopathy-associated dengue virus was more divergent from the others and was characterized by an Ala-->Val substitution at the position 173 of the envelope glycoprotein. This substitution mapped to the central domain 1 which was not known to be involved directly in envelope-receptor interaction.

Disseminated Penicillium marneffei infection in human immunodeficiency virus-infected children.

Disseminated infection with the fungus Penicillium marneffei is one of the most common opportunistic infections in human immunodeficiency virus (HIV) disease in northern Thailand. We report the clinical, laboratory and therapeutic features of 21 human immunodeficiency virus-infected children with disseminated P. marneffei who were prospectively followed. Significant clinical and laboratory features included generalized lymphadenopathy (90%), hepatomegaly (90%), body temperature > 38.5 degrees C (81%), papular skin lesions with central umbilication (67%), splenomegaly (67%), failure to thrive (52%), severe anemia (hemoglobin < 60 g/liter) (43%) and thrombocytopenia (platelet count < 0.5 x 10(11)/liter) (21%). The response rate in patients who were treated with appropriate antifungal therapy (amphotericin B, fluconazole or ketoconazole) was 82%. No relapse was observed in patients given ketoconazole prophylactically. Skin lesions, usually papules with central necrotic umbilication, provide the most significant clue to the diagnosis. Early diagnosis based on finding P. marneffei in the skin smear or lymph node provides the basis for prompt administration of antifungal therapy and improved outcome.

PIP: This report describes the epidemiology of Penicillium marneffei infections among HIV infected children who were seen at Chiang Mai University Hospital, Thailand, between April 1989 and January 1995. HIV infections among children 18 months old and older were determined by both enzyme-linked immunosorbent assay and particle agglutination tests. Confirmation of HIV infection was made among younger children by signs and symptoms and repeated reactive serum tests. Diagnosis of P. marneffei infection was determined by isolation of the organism from clinical blood or tissue specimens. Antifungal agents were administered and improvement was recorded. There were 23 cases of P. marneffei among the 362 children diagnosed with HIV infection during the study period. One case was a non-HIV infected girl and another was a thalassemic patient who had received an HIV infected blood transfusion. The remaining 21 children acquired the infection perinatally. All mothers of the 21 children had acquired the HIV infection as prostitutes or from husbands who used prostitutes. All 21 children had clinical cases of HIV infection at the onset of the P. marneffei infection. The median time of presentation was 32 months. Fever was a primary symptom. 67% had skin lesions and most lesions were on the face and extremities. Other laboratory findings are reported. 9 of the 21 children had other HIV-related opportunistic infections diagnosed at the same time as the diagnosis of P. marneffei. There were 4 cases of Salmonella bacteremia, 2 cases of cryptosporidiosis, 1 case of Pseudomonas aeruginosa bacteremia, 1 case of Pneumocystis carinii and cytomegalovirus pneumonia, and 1 case of nontyphoid Salmonella bacteremia and herpes zoster. All 7 culture-proved patients who did not receive antifungal therapy died. 9 culture-proved and 3 other cases responded to antifungal treatment. Findings suggest that P. marneffei infection should be included as another AIDS-defining illness. The case fatality rate of patients with P. marneffei infection was very high, mostly due to late diagnosis.

Histopathologic spectrum of AIDS-associated lesions in Maharaj Nakorn Chiang Mai Hospital.

The histopathological alterations in various organs and the presence of AIDS-associated lesions were studied in 86 biopsy and 29 necropsy specimens of AIDS patients. The most common cancer seen in this study were malignant lymphomas (4% of cases) with development of extensive extranodal lymphomatous involvement from the outset. Although a preponderance of high grade B-cell pathologic subtypes is found in AIDS-associated lymphoma, we also report the first case of T-lymphoblastic lymphoma with a picture of acute lymphoblastic leukemia (T-ALL). Tuberculosis (34% of cases) was the most common opportunistic infection presented in tissue sections, and the majority of tissue biopsies revealed poorly organized granulomas and extensive necrosis with numerous bacilli. Penicilliosis (20% of cases) appeared to be the most common cutaneous lesion with multiple organ involvement. The involved organs showed a partially anergic tissue reaction characterized by poorly formed granulomas with diffuse infiltrate of fungi-laden macrophages and lymphoid cell depletion. This organism has to be distinguished from Histoplasma capsulatum and other yeast-form fungi. Co-existing cytomegalovirus and P. carinii infections were the predominant findings in lung necropsy specimens from pediatric patients who died from AIDS. A major pathologic feature in this group was diffuse alveolar damage stage II to III with heavy loads of organism and extensive lymphoplasmacytic infiltration.

First cases of spotted fever group rickettsiosis in Thailand.

The first three cases of spotted fever group rickettsiosis from Thailand are reported. The patients presented with fever, headache, lymphadenopathy, and petechial maculopapular rash. One patient also had an eschar and overt evidence of confusion. An indirect fluorescent antibody test, an indirect immunoperoxidase test, and an enzyme-linked immunosorbent assay demonstrated a broad, strong reactions of the sera of the patients with spotted fever group rickettsia antigens of many species, but not with antigens of typhus or scrub typhus rickettsiae. All three patients responded to treatment with a single dose of doxycycline.

Studies on serological cross-reaction in sequential flavivirus infections.

Acute- and convalescent-phase sera from patients with dengue (DEN) hemorrhagic fever (DHF) and Japanese encephalitis (JE) that contained pre-existing flavivirus antibodies were tested for cross-reacting antibodies to DEN, JE and yellow fever (YF) viruses by a neutralization (N) test. A fourfold or greater rise in N antibody titer in the convalescent-phase was considered significant. Of 39 DHF cases, obtained at Chiang Mai University Hospital, Thailand, 15 (38.5%) showed a rise in DEN antibody titer, while another 15 (38.5%) showed a significant rise in both DEN and JE N antibody titers. On the other hand, eight (61.5%) of 13 JE cases obtained at the same Hospital, showed a significant rise in JE antibody titer, while two (15.4%) showed a significant rise in both DEN and JE antibody titers. Sucrose gradient centrifugation and fractionation of these two cross-reactive JE sera revealed that IgM class antibody was specific for JE, while IgG class antibody was cross-reactive. Of three JE cases with pre-existing YF antibody obtained in Okinawa, Japan, two showed a significant rise in YF and JE antibodies. Both IgM and IgG class antibodies to YF virus were elevated. These results indicate that the cross-reactivity among flaviviruses in different subgroups (complexes), was observed quite often, even by the N test, in sequential flavivirus infection.

Late manifestations of HIV in Asia and the Pacific.

PIP: Late-stage HIV infection is characterized by profound immunodeficiency with a progressive and irreversible decline in the CD4 count, functional impairment of cellular and humoral immunity, and evidence of increased viral replication, with the appearance of p24 antigenemia and increasing levels of beta(2)-microglobulin and neopterin. These changes are associated with increased susceptibility to many infections, the emergence of malignancies, and neurological complications due to the direct infection of neural tissue with HIV. In Australia, opportunistic infections and malignancies account for 75% and 18% of AIDS diagnoses, respectively. Opportunistic infections and neurological involvement usually occur late in the illness and may be associated with disturbances of function of each part of the neuraxis. The detailed clinical nature of the involvement has been described in several recent reviews and is probably not different in the Asia-Pacific region. The most common opportunistic infections in Australia are Pneumocystis carinii pneumonia (PCP), esophageal candidiasis, toxoplasmosis, CMV infection, atypical mycobacteriosis, and cryptococcal meningitis. There are few data from Asian countries, but it seems that the most common opportunistic infections are tuberculosis, PCP, systemic Penicillium marneffei infection, and cryptococcal meningitis. There is little information from Asia on neurological conditions. Tuberculosis is probably the most significant threat to public health in Asia and the Pacific. Its management and prevention require ongoing planning and resources. To that end, a collaborative effort is called for to help resource-poor countries. Mycobacterial, fungal, viral, and protozoal infections are discussed, along with consideration of neurological complications, malignant disease, and late manifestations of HIV infection in children.^ieng

Applications of polymerase chain reaction for identification of dengue viruses isolated from patient sera.

A simple and sensitive procedure of reverse transcriptase polymerase chain reaction (RT-PCR) was developed previously such that all 4 serotypes of dengue viruses could be detected and their serotypes identified simultaneously in a single-step procedure. In this study we compared the RT-PCR with a conventional immunoperoxidase (PAP) staining method for the identification of dengue viruses currently isolated from patient sera. Sixty-six sera taken from dengue hemorrhagic fever (DHF) patients were subjected to virus isolation by inoculating onto C6/36 cell cultures. Screening for the presence of dengue viruses in culture fluids was done after 7 days of incubation by PAP staining using hyperimmune rabbit anti-dengue virus antibody as the primary reagent. Dengue viruses in positive cultures were further identified for their serotypes by PAP using type-specific monoclonal antibodies (MAb) and by RT-PCR. Thirty-two out of the 66 serum specimens tested (48.5%) were positive for dengue viruses. Of these, 5 were type 1 (DEN-1), 25 were type 2 (DEN-2) and 2 contained both DEN-1 and DEN-2. All cultures that were positive by PAP method were also positive by RT-PCR and vice versa. Thus, the results obtained by RT-PCR were in good agreement with those by PAP. It is important to point out that while all 5 DEN-1 isolates reacted readily with the MAb 1F1, only 2 of them could be identified by the MAb 15F3. Our data suggest that antigenic variation among DEN-1 isolates occur frequently and this should be taken into consideration in the selection of appropriate type-specific MAb for serotyping of dengue viruses.(ABSTRACT TRUNCATED AT 250 WORDS)

The relative importance of various enteropathogens as a cause of diarrhoea in hospitalized children in Chiang Mai, Thailand.

PIP: A study of 208 children aged under 15 hospitalized with diarrhea and 108 matched controls was conducted at Chiang Mai University Hospital, Chiang Mai, Thailand from May 1983 to April 1984 to investigate the incidence, seasonal distribution, and causative agents of diarrhea. 1 or more enteropathogens were isolated from 121 (58%) diarrhea patients and from 32 (30%) controls. In diarrhea patients, Shigella spp. were most frequently isolated (22%) followed by enteropathogenic Escherichia coli (EPEC) (20%), rotavirus (18%), Campylobacter jejuni (7%), Salmonella (4%), Aeromonas (1%) and Plesiomonas shigelloides (1%). No Yersinia enterocolitica were found. Pathogens such as Norwalk agent, adenovirus, and enterotoxigenic E. coli (ETEC) were not sought. A concurrent study revealed ETEC in 3.2% of diarrheal children and 1.5% of controls. Parasites were identified in 11% of diarrhea patients; Giardia lamblia was most commonly found. In 32% of positive diarrhea and 19% of positive control cases more than 1 pathogen was isolated. Shigella was the least involved in cases with multiple infections. Only Shigella and rotavirus were found significantly more often in diarrhea cases than controls and their relation with age, season, and clinical presentation are reported. A high incidence of EPEC among control patients suggests common asymptomatic carriage. 2 diarrhea peaks occurred in the hot and cold seasons; the peak of Shigella diarrhea occurs in the summer, and may be related to the shortage of water at this time of year. Both shigellosis and rotavirus diarrhea patients had an acute onset of symptoms: cramps, convulsions, mucoid and bloody stools with high numbers of white and red blood cells were signficantly more common in shigellosis patients.^ieng

Outbreak of oral-oropharyngeal anthrax: an unusual manifestation of human infection with Bacillus anthracis.

An oral-oropharyngeal form of human anthrax is described in 24 individuals. The cases occurred as an epidemic in northern Thailand, concurrent with an epidemic of the common cutaneous form. This syndrome is a potentially fatal, febrile illness, characterized by a mucosal lesion in the oral cavity and/or oropharynx which can progress to pseudomembranous necrosis, and to cervical adenopathy and edema. Cattle and water buffaloes, recently arrived from Burma and eaten raw or undercooked, were the probable source of the infection. Determination of etiology was based on both microbiologic and epidemiologic evidence. The clinical syndrome and epidemiology are discussed.