Early-phase factors associated with pediatric severe dengue in the Thai-Myanmar cross-border region.

BACKGROUND: Dengue disease is caused by dengue virus, which is transmitted by Aedes mosquitoes in tropical and subtropical regions worldwide. Although most infected individuals have benign febrile illness or no apparent symptoms, a small percentage develop severe dengue, a potentially fatal condition that occurs after a febrile stage. Many studies have identified factors predicting dengue severity among different populations and time courses. To help find practical approaches applicable in remote settings, we focused on the investigation of early factors associated with severe dengue in Thai-Myanmar cross-border region. METHODS: This retrospective case-control study was performed to determine factors contributing to severe dengue in the pediatric population. We reviewed the hospital records of patients with dengue infection aged 0-19 years who were admitted to Maesot General Hospital, situated near the Thai-Myanmar cross-border region, between 2017 and 2022. Medical data during the first 5 days of illness and outcomes were collected and analyzed. RESULTS: This study included 144 patients with a serologically confirmed diagnosis of dengue infection, with 43 severe and 101 non-severe cases. Among biological factors, being an infant and belonging to an ethnic group in Myanmar showed a significant association with severe dengue in the univariable analysis. Multivariable logistic regression revealed that the presence of mucosal bleeding (adjusted OR 5.39, 95% CI 1.06-27.52, P = 0.043), a change in hematocrit ≥ 10% (adjusted OR 3.68, 95% CI 1.15-11.74, P = 0.028), and serum albumin < 35 g/L (adjusted OR 8.10, 95% CI 2.55-25.72, P < 0.001) during the first 5 days of illness were significantly associated with developing severe dengue. CONCLUSIONS: This study supports the use of certain WHO warning signs and hematocrit change during febrile phase to predict pediatric severe dengue in low-resource settings. Potential factors such as very young age and ethnic groups warrant further exploration to identify risks contributing to severe dengue infection.

Gametocyte prevalence and risk factors of P. falciparum malaria patients admitted at the Hospital for Tropical Diseases, Thailand: a 20-year retrospective study.

BACKGROUND: The incidence of malaria in Thailand has dramatically declined over the past two decades, and the goal is to eliminate malaria by 2025. Despite significant progress, one of the key challenges to malaria elimination are undetected gametocyte carriers. Human migration adds complexity to the malaria situation, as it not only sustains local transmission but also poses the risk of spreading drug-resistant parasites. Currently, no study has assessed the prevalence of gametocytes across multiple years in Plasmodium falciparum malaria patients in Thailand, and the risk factors for gametocyte carriage have not been fully explored. METHODS: Medical records of all P. falciparum malaria patients admitted from January 1, 2001 to December 31, 2020 at the Hospital for Tropical Diseases, Thailand, were retrospectively examined and a total of 1962 records were included for analysis. Both P. falciparum parasites and gametocytes were diagnosed by microscopy. A regression model was used to evaluate predictors of gametocyte carriage. RESULTS: The study demonstrated gametocyte prevalence in low malaria transmission areas. Nine risk factors for gametocyte carriage were identified: age between 15 and 24 years [adjusted odds ratio (aOR) = 1.96, 95% confidence interval (CI) 1.18-3.26], Karen ethnicity (aOR = 2.59, 95% CI 1.56-4.29), preadmission duration of fever > 7 days (aOR = 5.40, 95% CI 3.92-7.41), fever on admission (> 37.5 °C) (aOR = 0.61, 95% CI 0.48-0.77), haemoglobin ≤ 8 g/dL (aOR = 3.32, 95% CI 2.06-5.33), asexual parasite density > 5000-25,000/µL (aOR = 0.71, 95% CI 0.52-0.98), asexual parasite density > 25,000-100,000/µL (aOR = 0.74, 95% CI 0.53-1.03), asexual parasite density > 100,000/µL (aOR = 0.51, 95% CI 0.36-0.72), platelet count ≤ 100,000/µL (aOR = 0.65, 95% CI 0.50-0.85, clinical features of severe malaria (aOR = 2.33, 95% CI 1.76-3.10) and dry season (aOR = 1.41, 95% CI 1.10-1.80). An increasing incidence of imported transnational malaria cases was observed over the past two decades. CONCLUSIONS: This is the first study to determine the prevalence of gametocytes among patients with symptomatic P. falciparum malaria, identify the risk factors for gametocyte carriage, and potential gametocyte carriers in Thailand. Blocking transmission is one of the key strategies for eliminating malaria in these areas. The results might provide important information for targeting gametocyte carriers and improving the allocation of resources for malaria control in Thailand. This study supports the already nationally recommended use of a single dose of primaquine in symptomatic P. falciparum malaria patients to clear gametocytes.

A Phase 3, Double-Blind, Randomized Study of Arterolane Maleate-Piperaquine Phosphate vs Artemether-Lumefantrine for Falciparum Malaria in Adolescent and Adult Patients in Asia and Africa.

BACKGROUND: Artemisinins, which are derived from plants, are subject to risk of supply interruption due to climatic changes. Consequently, an effort to identify a new synthetic antimalarial was initiated. A fixed-dose combination of arterolane maleate (AM), a new synthetic trioxolane, with piperaquine phosphate (PQP), a long half-life bisquinoline, was evaluated in patients with uncomplicatedPlasmodium falciparummalaria. METHODS: In this multicenter, randomized, double-blind, comparative, parallel-group trial, 1072 patients aged 12-65 years withP. falciparummonoinfection received either AM-PQP (714 patients) once daily or artemether-lumefantrine (A-L; 358 patients) twice daily for 3 days. All patients were followed up until day 42. RESULTS: Of the 714 patients in the AM-PQP group, 638 (89.4%) completed the study; of the 358 patients in the A-L group, 301(84.1%) completed the study. In both groups, the polymerase chain reaction corrected adequate clinical and parasitological response (PCR-corrected ACPR) on day 28 in intent-to-treat (ITT) and per-protocol (PP) populations was 92.86% and 92.46% and 99.25% and 99.07%, respectively. The corresponding figures on day 42 in the ITT and PP populations were 90.48% and 91.34%, respectively. After adjusting for survival ITT, the PCR-corrected ACPR on day 42 was >98% in both groups. The overall incidence of adverse events was comparable. CONCLUSIONS: AM-PQP showed comparable efficacy and safety to A-L in the treatment of uncomplicatedP. falciparummalaria in adolescent and adult patients. AM-PQP demonstrated high clinical and parasitological response rates as well as rapid parasite clearance. CLINICAL TRIALS REGISTRATION: India. CTRI/2009/091/000101.

Plasma levels of Galectin-9 reflect disease severity in malaria infection.

BACKGROUND: Galectin-9 (Gal-9) is a ß-galactoside-binding lectin that interacts with sugar moieties on glycoproteins and glycolipids of cells and pathogens. Gal-9 is known as an immune modulator that induces cell death via interaction with T cell immunoglobulin and mucin domain-3 (Tim3), a co-inhibitory receptor, and it inhibits production of several pro-inflammatory cytokines (TNF, IL-6 and IL-1α) and enhances production of IL-10. To understand the immune pathology of malaria, the Gal-9 in plasma was measured. METHODS: Plasma samples and clinical parameters were obtained from 50 acute malaria cases (nine severe and 41 uncomplicated cases) from Thailand at three time points: day 0, day 7 and day 28. Gal-9 levels were determined by ELISA. A total of 38 species of cytokines and chemokines were measured using a BioPlex assay. RESULTS: Gal-9 levels were higher at day 0 compared to day 7 and day 28 (P < 0.0001). Gal-9 levels were also higher in severe malaria (SM) cases compared to uncomplicated (UM) cases at day 0 and day 7 (923 vs 617 pg/mL; P = 0.03, and 659 vs 348 pg/mL; P = 0.02 respectively). Median Gal-9 levels were higher in patients with blood urea nitrogen to creatinine ratio (BUN/creatinine) ≥20 (mg/dL) than in patients with BUN/creatinine <20 (mg/dL) at day 0 (817.3 vs 576.2 pg/mL, P = 0.007). Gal-9 was inversely significantly correlated with chloride levels in both SM and UM cases (r s = -0.73 and r s = -0.46, respectively). In both UM and SM cases, Gal-9 was significantly associated with pro- and anti-inflammatory cytokines and chemokines such as TNF, IL-6, IFN-α2, IFN-γ, IL-1Ra and IL-10. These correlations were observed at day 0 but disappeared at day 28. CONCLUSIONS: Gal-9 is released during acute malaria, and reflects its severity. This elevation of Gal-9 in acute malaria infection raises the possibility of its role in termination of the immune response by binding to Tim-3, a receptor of Gal-9.

Schizontemia as an indicator of severe malaria.

We conducted this study to determine if the finding of schizontemia could be used as an indicator of severe falciparum malaria. We enrolled 250 patients with severe falciparum malaria and 250 patients with umcomplicated falciparum malaria into the study. Severe falciparum malaria was defined following World Health Organization criteria (2010). Of the 250 patients with severe falciparum malaria, 99 (39.6%) had schizontemia on admission. Of the 250 patients with uncomplicated falciparum malaria, 0 (0%) had schizontemia (p<0.05). Schizontemia was also found to be significantly correlated with parasite density, severe malaria, impaired consciousness, pulmonary edema, hypoglycemia, jaundice and hemoglobinuria (p<0.05). Schizontemia may be considered as an indicator of severe malaria.

Risk factors of shock in severe falciparum malaria.

The objective of this study was to determine the risk factors for the development of shock in adult patients admitted with severe falciparum malaria. As an unmatched case-control study, the records of patients who were admitted to the Bangkok Hospital for Tropical Diseases, Thailand, between the years 2000-2010, were reviewed. One hundred patients with severe falciparum malaria and shock, and another 100 patients with severe malaria but without shock were studied. Demographics, presenting symptoms, physical observations, and laboratory data of these patients were analyzed. Five risk factors for the development of shock were identified: female gender (OR 6.16; 95% CI 3.17-11.97), red cell distribution width (RDW) >15% (adjusted OR 2.90; 95% CI 1.11-7.57), anorexia (adjusted OR 2.76; 95% CI 1.03-7.39), hypoalbuminemia (adjusted OR 2.19; 95% CI 1.10-4.34), and BUN-creatinine ratio >20 (adjusted OR 2.38; 95% CI 1.22-4.64). Diarrhea was found to be a protective factor (adjusted OR 0.33; 95% CI 0.14-0.78). Metabolic acidosis was only weakly correlated to mean arterial blood pressure on admission (r(s) = 0.23). Female gender was the strongest risk factor for the development of shock. We concluded that female gender, RDW >15%, anorexia, hypoalbuminemia, and BUN-creatinine ratio >20 were risk factors of shock development in severe falciparum malaria.

Factors associated with cerebral malaria.

We conducted a retrospective unmatched case-control study using the medical records of patients admitted to the Hospital for Tropical Diseases, Mahidol University, Bangkok, Thailand to investigate factors associated with cerebral malaria. The records of 137 patients with severe Plasmodium falciparum without cerebral malaria and 35 patients with cerebral malaria hospitalized during 1997-2005 were reviewed and compared. Ten factors associated with cerebral malaria were identified: pulmonary edema [odds ratio (OR)= 13.8; 95% confidence interval (CI): 1.3-143.2], splenomegaly (OR=3.7; 95% CI: 1.3-44.7), fever (OR=3.3; 95% CI: 1.7-14.3), day 1 malarial density < or = 249,999/microl (OR=1.6; 95% CI: 1.1-14.6), day 2 malarial density < or =249,999/microl (OR=3.4; 95% CI: 1.3-35.1), dyspnea (OR=1.4; 95% CI: 1.2-12.1), hepatomegaly (OR=1.8; 95% CI: 0.2-12.1), being a referred patient (OR=1.3; 95% CI: 1.0-2.2), a higher systolic blood pressure (OR=1.2; 95% CI: 1.0-2.1) and a higher body mass index (OR=1.6; 95% CI: 1.0-2.6). Pulmonary edema was the strongest factor associated with cerebral malaria in our study. Clinicians who treat patients with severe Plasmodium falciparum malaria should be aware these factors are associated with cerebral malaria.

Sexual behavior of foreign backpackers in the Khao San Road area, Bangkok.

Travelers play a role in the spread of sexually transmitted diseases, including HIV because of having unprotected sex. We studied the incidence of casual sex among foreign backpack tourists in the Khao San Road area of Bangkok, Thailand. We also evaluated their attitudes about sexual health and their actual practices. A cross sectional study was conducted using a self-administered, anonymous questionnaire. The target population was backpackers aged > or =18 years, from Europe, North America and Australia. In total, 415 questionnaires were filled out and analyzed. Sixty-four percent of participants were male, the overall median age was 27 years and the mean duration of stay was 14.6 days. One hundred seven respondents (25%) had casual sex while staying in Thailand; of these, 55% always used condoms. The selection of sex partner influenced the use of condoms. The highest rate of condom use was among backpackers who had sex with sex workers (63%), while those who had sex with their travel partners had the lowest rate of condom use (35.6%). One-fourth of backpackers in our study had casual sex during their trip. Their attitudes towards safe sex practices were not ideal. Methods to change attitudes and behavior about unprotected sex need to be explored in this population.

Arterolane maleate plus piperaquine phosphate for treatment of uncomplicated Plasmodium falciparum malaria: a comparative, multicenter, randomized clinical trial.

BACKGROUND: Artemisinin-based combination therapy is the first-line treatment for uncomplicated falciparum malaria. This study assessed the antimalarial efficacy and safety of a combination of 150 mg of arterolane maleate and 750 mg of piperaquine phosphate (AM-PQP) in comparison to Coartem (artemether and lumefantrine) in patients with acute uncomplicated P. falciparum malaria. METHODS: In this open-label, randomized, multicentric, parallel group clinical trial, 240 patients were randomized to receive AM-PQP (160 patients) or Coartem (80 patients). Patients with P. falciparum monoinfection and initial parasite densities ranging from 1000 to 100 000 asexual parasites/µL of blood were followed for 28 days. Polymerase chain reaction-corrected adequate clinical and parasitologic response on day 28, parasite clearance time, and fever clearance time were evaluated. RESULTS: A total of 151 (94.4%) of 160 patients in the AM-PQP group completed the trial, while 77 (96.3%) of 80 patients in the Coartem group completed the trial. No treatment failure was noted in the AM-PQP group, while one patient receiving Coartem failed treatment on day 28. There was no difference in the median parasite clearance time (30 hours in both groups) or median fever clearance time (24 hours in both groups) after administration of the 2 study treatments. CONCLUSIONS: The available data support the evaluation of a drug combination in a larger population as a fixed-dose combination. Clinical Trials Registration. CTRI/2007/091/000031.

Activation of nuclear factor kappa B in peripheral blood mononuclear cells from malaria patients.

BACKGROUND: Malaria parasites and their products can activate a specific immune response by stimulating cytokine production in the host's immune cells. Transcription nuclear factor kappa B (NF-κB) is an important regulator for the control of many pro-inflammatory genes, such as interleukin-1 (IL-1) and tumor necrosis factor (TNF). The activation and expression of NF-κB p65 in peripheral blood mononuclear cells (PBMCs) of malaria patients were investigated and correlated with the levels of IL-10 and TNF to study the nature of NF-κB p65 and its linkage to inflammatory cytokines. METHODS: The sample group comprised 33 patients admitted with malaria caused by Plasmodium vivax (n = 11), uncomplicated Plasmodium falciparum (n = 11), and complicated Plasmodium falciparum (n = 11). Peripheral blood was collected at admission and on day 7 for PBMC isolation. Healthy subjects were used as a control group. The expressions of NF-κB p65 in the PBMCs from malaria patients and the plasma levels of IL-10 and TNF were measured by using enzyme-linked immunosorbent assay (ELISA). The immunofluorescence technique was used to determine NF-κB nuclear translocation. RESULTS: At admission, patients with P. vivax and uncomplicated P. falciparum had significantly elevated phospho-NF-κB p65 levels in the PBMCs compared with those of healthy controls. However, patients with complicated P. falciparum malaria had decreased levels of phospho-NF-κB p65. On day 7 post-treatment, significantly increased phospho-NF-κB p65 was found in the PBMCs of patients with complicated P. falciparum, compared with healthy controls. The plasma level of IL-10 was elevated in day 0 in patients with complicated P. falciparum malaria and was found to be negatively correlated with phospho-NF-κB p65 level (rs = -0.630, p = 0.038). However, there was no correlation between phospho-NF-κB p65 expression and TNF level in patients with complicated P. falciparum malaria. CONCLUSIONS: This is the first report demonstrating alterations in NF-κB p65 activity in the PBMCs of malaria patients. The altered lower features of NF-κB p65 in the PBMCs of patients with complicated P. falciparum at admission could be due to a suppressive effect of high IL-10 associated with complicated P. falciparum malaria.

Mimicking platelet indices in patients with malaria and dengue hemorrhagic fever: characteristics and clinical applications.

BACKGROUND: Although platelet indices are routinely available using automated blood cell counters, the clinical applications of these parameters for malaria and dengue hemorrhagic fever (DHF) have not been substantially implemented. We conducted this study to investigate the potential role of platelet indices as a prognostic marker in adult patients with Plasmodium vivax malaria, Plasmodium falciparum malaria, and DHF admitted to the Hospital for Tropical Diseases, Bangkok, Thailand. METHODS: We enrolled 219 eligible patients, comprising 96 with P. falciparum malaria, 71 with P. vivax malaria, and 52 with DHF. We evaluated the study groups' baseline clinical features and alterations of platelet indices during the first 4 days of admission. RESULTS: Upon admission, the initial laboratory findings showed no statistically significant difference in platelet count (PC), plateletcrit (PCT), or platelet distribution width (PDW) between patients with P. vivax and P. falciparum; however, mean platelet volume (MPV) was significantly higher in patients with P. falciparum. Comparisons of the initial platelet indices in malaria and DHF showed that only PC and PCT were significantly lower in DHF. Although MPV in DHF tended to be lower than in malaria, a statistically significant difference was observed only with P. falciparum. Moreover, the results also showed no significant alterations in the platelet indices among the study groups during the first 4 days of admission. CONCLUSIONS AND RECOMMENDATIONS: Clinical presentations of DHF and malaria are nonspecific and may overlap with other common tropical diseases. Alterations of initial platelet indices may be investigated in P. vivax and P. falciparum malaria mimicking DHF. Although a significant reduction in PC and PCT in DHF might be a clue for differential diagnosis of malaria, the use of MPV and PDW might be impractical. We suggest that appropriate laboratory diagnoses for malaria and dengue infections are still needed for the differential diagnosis of acute febrile patients who have a risk of malaria or dengue infections. To clarify the clinical utility of platelet indices in patients with dengue and malaria, further studies are required that particularly include patients with different severities, geographical areas, and levels of health care settings.

Factors associated with acute renal failure in falciparum malaria infected patients.

To identify factors associated with acute renal failure among patients with severe falciparum malaria (MARF), we studied 189 severe malaria patients admitted to the Hospital for Tropical Diseases, Faculty of Tropical Medicine, Mahidol University, in Bangkok, Thailand. Among these, 63 had MARF, and 126 did not. Baseline clinical demographics and laboratory variables were evaluated with univariate analysis. Logistic regression was used to ascertain adjusted odds ratios. By univariate analysis, factors associated with MARF included male gender, fever duration > 4 days, patients who lived in a non-endemic area prior to malaria infection, body mass index > 18.5 kg/m(2), oliguria, abdominal pain, impaired consciousness, jaundice, anemia, liver enlargement, total white blood cell count > 10x10(9)/1, total bilirubin > 3 mg/dl, aspartate aminotransferase > 120 U/l, alanine aminotransferase > 120 U/l, albumin < 3 g/dl, fever clearance time >72 hours, and parasite clearance time > 72 hours. A hemoglobin > 10 g/dl, patients living in a malaria endemic area, non-oliguria on the day of admission, and splenomegaly were negatively associated with MARF. After multivariate logistic regression, oliguria during the first 24 hours of admission and a history of living in a nonendemic area prior to malarial infection were factors associated with MARF. We conclude the most significant factors associated with MARF were oliguria on the day of admission and living in a non-endemic area prior to malaria infection.

Arterolane, a new synthetic trioxolane for treatment of uncomplicated Plasmodium falciparum malaria: a phase II, multicenter, randomized, dose-finding clinical trial.

BACKGROUND: Drug-resistant Plasmodium falciparum malaria necessitates development of novel drugs for treatment.The present study assessed the efficacy and safety of 3 dose levels of arterolane (RBx 11160), a synthetic trioxolane, for treatment of acute uncomplicated falciparum malaria. METHODS: In this randomized, double-blind, multicenter, parallel-group, dose-finding, phase II trial, 230 patients from 4 centers in Thailand, India, and Tanzania (mainland and Zanzibar) received either 50 mg (n=78), 100mg (n=76), or 200 mg (n=76) of arterolane once daily for 7 days. Patients (aged 13-65 years) with asexual parasite density of 1000-100,000 parasites/microL were included and were followed up for 28 days. The median time to 90% parasite clearance (PC90) was evaluated. RESULTS: The median PC90 was longer in the group receiving the 50-mg dose (19.4 h), compared with the groups receiving the 100-mg dose (12.8 h) and 200-mg dose (12.6 h) (P < .01). The polymerase chain reaction-corrected adequate clinical and parasitological responses on day 28 were 63%, 71%, and 72% for the groups receiving the 50-mg, 100-mg, and 200-mg doses, respectively, by intention-to-treat analysis (odds ratio, 1.55; 95%confidence interval, 0.78-3.06, for comparison of the 200-mg and 50-mg dose groups). Treatment was generally well tolerated. No patient died or experienced any serious adverse event. Mild complaints were reported in <10%of the patients and were similar in the 3 groups. Biochemistry and hematological analyses did not show any signof drug toxicity in any patient. CONCLUSION: Arterolane at daily doses of 100 and 200 mg is a rapidly acting, effective, and safe synthetic antimalarial drug, which may potentially represent an alternative to artemisinin derivatives in antimalarial combination therapy. TRIAL REGISTRATION: ClinicalTrials.gov identifier NCT00362050.

Long term primaquine administration to reduce Plasmodium falciparum gametocyte transmission in hypoendemic areas.

Artemesinin-combination therapies (ACTs) for falciparum malaria reduce gametocyte carriage, and therefore reduce transmission. Artemisinin derivatives act only against young gametocytes, but primaquine acts against mature gametocytes (which are usually present in the circulation at the time the patient presents for treatment). Both artemisnin derivatives and primaquine have short half-lives (less than 1 hour and 8 hours, respectively). Therefore, asexual parasites and young gametocytes may remain after completing ACT. Single dose of primaquine (0.5-0.75 mg base/kg) at the end of ACT can kill only mature gametocytes (if present) but cannot kill young gametocytes (if present). Remaining asexual forms and sequestered young gametocytes remaining after completion of ACT may develop into mature gametocytes 7-15 days later. Some patients have the first appearance of gametocytemia 4-8/day after completion of ACT. Thus, additional doses of primaquine (0.5-0.75 mg base/kg) given 15-18 days after or concurrently with 3 day-ACT respectively or given 15-22 days after or concurrently with 7 day-ACT respectively may be beneficial in killing the remaining mature gametocytes and thus contribute to interruption of P. falciparum gametocyte transmission more affectively than giving only a single dose of primaquine just after completing ACT.

Management of Plasmodium knowlesi malaria without PCR confirmation.

Plasmodium knowlesi morphologically resembles P. malariae; PCR assays are able to differentiate between the 2 species correctly. However, PCR is not available in many hospitals in P. knowlesi endemic areas, particularly in Southeast Asia. In places where PCR is not available, anti-malarial drugs for P. malariae or other non-P. falciparum or P. falciparum species are effective against P. knowlesi. Even with a wrong diagnosis of another malaria species by light microscopy instead of P. knowlesi, the antimalarial drugs given are still effective for treating P. knowlesi infection.

Vitamin K injection in spontaneous bleeding and coagulopathy in severe malaria: pros and cons.

Not all clinicians give vitamin K to severe malaria patients with systemic bleeding. Vitamin K injections may not be useful to stop bleeding in severe malaria patients with predominant hepatocellular jaundice. However, vitamin K may be justified in bleeding patients who have prolonged fasting of more than 3-7 days, underlying malnutrition, or predominant cholestatic jaundice. The decision to give vitamin K to severe malaria patients with systemic bleeding should be based on underlying diseases, type of jaundice, risk for vitamin K deficiency, and allergy to the drug.

Cruveilhier-Baumgarten syndrome in a cirrhotic patient taking alcohol with Boesenbergia pundurata.

Cruveilhier-Baumgarten syndrome (CBS) is a rare complication of cirrhosis. We reported a case of CBS who came to hospital with progressive ascites, jaundice, fever and upper gastrointestinal bleeding. The cause of cirrhosis and hepatitis might be due to alcohol and possibly local Thai herb [Boesenbergia pundurata (Roxb.) Schitr or Krachaidum].

Changes in platelet count in uncomplicated and severe falciparum malaria.

This study investigated alterations in platelet counts pre- and post-treatment with artemisinin derivatives in uncomplicated and severe falciparum malaria. Serial platelet counts were taken over 4 weeks for 110 uncomplicated and 110 severe falciparum malaria patients admitted to the Hospital for Tropical Diseases during 2005-2008. On admission, prior to treatment, thrombocytopenia was found in 73.6% of uncomplicated falciparum malaria patients and 90.9% of severe falciparum malaria cases. Platelet levels significantly lower in severe malaria cases. Although initial platelet counts were lower than normal in both study groups, they slowly increased significantly over time, and approached normal levels by several weeks post-treatment. No bleeding was evident during treatment, and none of the patients required a platelet transfusion. Platelet transfusions are not required for malaria patients with thrombocytopenia who have no bleeding.

Factors associated with acute renal failure in severe falciparum [corrected] malaria patients.

Acute renal failure (ARF) is a common cause of morbidity and mortality in severe malaria infection. We evaluated factors associated with acute renal failure in severe malaria by comparing patients with severe malaria with and without ARF admitted to the Hospital for Tropical Diseases, Bangkok, Thailand. Nine hundred fifteen severe malaria patients were included in the study, of whom 195 had ARF and 720 did not have ARF. We found jaundice, anemia, hypoalbuminemia, hyponatremia, hyperkalemia, acidosis, leukocytosis, elevated transaminases (SGOT and SGPT) and cerebral malaria, were significantly associated with ARF among patients with severe malaria (p < 0.05). Patients who have ARF and any of these clinical or laboratory manifestations of severe malaria should be monitored and managed properly, since early detection and treatment may reduce morbidity and mortality.

Primaquine administration after falciparum malaria treatment in malaria hypoendemic areas with high incidence of falciparum and vivax mixed infection: pros and cons.

Mixed infections of Plasmodium falciparum and Plasmodium vivax is high (approximately 30%) in some malaria hypoendemic areas where the patients present with P. falciparum malaria diagnosed by microscopy. Conventional treatment of P. falciparum with concurrent chloroquine and 14 days of primaquine for all falciparum malaria patients may be useful in areas where mixed falciparum and vivax infections are high and common and also with mild or moderate G6PD deficiency in the population even with or without subpatent vivax mixed infection. It will be possibly cost-effective to reduce subsequent vivax illness if the patients have mixed vivax infection. Further study to prove this hypothesis may be warranted.