Assessment of an Immuno-Diagnostic Method for Hookworm-Related Cutaneous Larva Migrans Using Crude Extracts of Ancylostoma caninum.

People can become infected with cutaneous larva migrans (CLM) through skin penetration by the infective zoonotic larvae of hookworms. Few studies have investigated CLM's immunodiagnosis, and the existing studies were limited to crude somatic or excretory/secretory antigens (Ags) from adult worms. Here, we aimed to develop an indirect enzyme-linked immunosorbent assay (ELISA) to differentiate and diagnose hwCLM by detecting immunoglobulin (Ig)E, IgG, and IgG subclasses 1-4 (IgG1-4) against the somatic Ag of adult Ancylostoma caninum checkerboard titrations of adult A. caninum worm extract. Pooled serum controls were immunocharacterized using an indirect ELISA. The IgG1-4 and IgE results were unsatisfactory; however, the use of total IgG achieved results comparable to those of immunoblotting. Thus, we continued to analyze the IgG-ELISA using serum samples from patients with hwCLM and heterologous infections as well as from healthy controls. The sensitivity and excellent specificity of the total IgG-ELISA were 93.75% and 98.37%, respectively, and its positive and negative predictive values were 75% and 99.67%, respectively. Antibodies from five cases of angiostrongyliasis, gnathostomiasis, and dirofilariasis cross-reacted with the somatic Ag of adult A. caninum. This new assay can adequately serodiagnose hwCLM when combined with clinical features and/or histological examination.

Atypical complication in an adult patient with dengue and autoimmune hemolytic anemia: a case report.

Severe dengue infection is associated with life-threatening complications, including severe bleeding. The bleeding tendency is typically associated with the shock phase of infection, for which blood replacement may be needed. However, repetitive blood transfusion can lead to volume overload. Administration of recombinant activated factor VII (rFVIIa) might be used to counteract bleeding without inducing volume overload. We describe the case of a patient with severe dengue infection who presented with intractable bleeding; he was initially treated with massive blood transfusions, which resulted in volume overload. He was then treated with rFVIIa to reverse the bleeding. During the second week of his hospitalization, his hematocrit dropped precipitously, and autoimmune hemolytic anemia was diagnosed. Supportive treatment was provided until recovery. Autoimmune hemolytic anemia is a rare complication in adult patients with dengue. Supportive care was effective for this atypical complication.

Evaluation of Hematocrit in Adults with Dengue by a Laboratory Information System.

The implementation of a laboratory information system (LIS) at the Hospital for Tropical Diseases in Thailand provides valuable medical resources, particularly for dengue. Hematocrit (Hct), which is often derived from hemoglobin (Hgb), is important in the diagnosis and management of dengue. This study aimed to evaluate the Hct value obtained from the LIS automated analyzer. We prospectively enrolled 163 hospitalized adults with dengue, for whom 1,141 real-time complete blood count (CBC) results were obtained via a hematology analyzer and updated in the LIS database. The median (interquartile range (IQR)) duration of analytic turnaround times (TATs) was 40.0 (30.0-53.0) minutes. Linear regression analysis indicated a significant relationship between Hgb and Hct with a coefficient of determination (Pearson's R 2) of 0.92 at red blood cell distribution width (RDW) ≤18, but Pearson's R 2 decreased to 0.78 at RDW >18. The Hct calculated from the three-fold conversion method and from the analyzer had a Pearson's R 2 of 0.92. At Hgb <12 g/dl and ≥16 g/dl, a greater difference between the two Hct values was observed, with median (IQR) differences of -0.8% (-1.9%-0.2%) and 0.8% (-0.1%-1.7%), respectively (P value <0.05). In conclusion, the Hgb and Hct of patients with dengue were highly correlated at RDW ≤18. The Hct calculated from the three-fold conversion method and from the analyzer had an excellent relationship, except when the Hgb was <12 g/dl or ≥16 g/dl. Apart from routine CBC evaluation, the LIS could help for accurate data collection in clinical research and development.

False-positive dengue IgM test result in a patient with systemic lupus erythematosus: a case report.

Dengue virus infection most commonly has mild-to-moderate nonspecific clinical presentations that overlap with other diseases. Dengue-specific tests are commonly used for those patients with acute febrile illness in dengue-endemic areas. There is one study in vitro that showed a false-positive dengue-immunoglobulin M (dengue IgM) test for blood from a patient with systemic lupus erythematosus (SLE). Here, we demonstrated a false-positive dengue IgM test in a patient with SLE. The patient had fever, cytopenia, and a skin rash, but her clinical variables more closely matched with the criteria for SLE than the dengue infection. Vasculitis-like-lesions supported prednisolone administration and her clinical symptoms improved. This case highlights that some patients with SLE can be misdiagnosed as having a viral infection. These two diseases have similar clinical findings, such as acute febrile illness, but they are different in terms of their treatments and disease prognosis.

Gametocyte clearance in uncomplicated and severe Plasmodium falciparum malaria after artesunate-mefloquine treatment in Thailand.

Artemisinin-based combination therapy (ACT) is currently promoted as a strategy for treating both uncomplicated and severe falciparum malaria, targeting asexual blood-stage Plasmodium falciparum parasites. However, the effect of ACT on sexual-stage parasites remains controversial. To determine the clearance of sexual-stage P. falciparum parasites from 342 uncomplicated, and 217 severe, adult malaria cases, we reviewed and followed peripheral blood sexual-stage parasites for 4 wk after starting ACT. All patients presented with both asexual and sexual stage parasites on admission, and were treated with artesunate-mefloquine as the standard regimen. The results showed that all patients were asymptomatic and negative for asexual forms before discharge from hospital. The percentages of uncomplicated malaria patients positive for gametocytes on days 3, 7, 14, 21, and 28 were 41.5, 13.1, 3.8, 2.0, and 2.0%, while the percentages of gametocyte positive severe malaria patients on days 3, 7, 14, 21, and 28 were 33.6, 8.2, 2.7, 0.9, and 0.9%, respectively. Although all patients were negative for asexual parasites by day 7 after completion of the artesunate-mefloquine course, gametocytemia persisted in some patients. Thus, a gametocytocidal drug, e.g., primaquine, may be useful in combination with an artesunate-mefloquine regimen to clear gametocytes, so blocking transmission more effectively than artesunate alone, in malaria transmission areas.

Predictive score of uncomplicated falciparum malaria patients turning to severe malaria.

In acute uncomplicated falciparum malaria, there is a continuum from mild to severe malaria. However, no mathematical system is available to predict uncomplicated falciparum malaria patients turning to severe malaria. This study aimed to devise a simple and reliable model of Malaria Severity Prognostic Score (MSPS). The study was performed in adult patients with acute uncomplicated falciparum malaria admitted to the Bangkok Hospital for Tropical Diseases between 2000 and 2005. Total 38 initial clinical parameters were identified to predict the usual recovery or deterioration to severe malaria. The stepwise multiple discriminant analysis was performed to get a linear discriminant equation. The results showed that 4.3% of study patients turned to severe malaria. The MSPS = 4.38 (schizontemia) + 1.62 (gametocytemia) + 1.17 (dehydration) + 0.14 (overweight by body mass index; BMI) + 0.05 (initial pulse rate) + 0.04 (duration of fever before admission) - 0.50 (past history of malaria in last 1 year) - 0.48 (initial serum albumin) - 5.66. Based on the validation study in other malaria patients, the sensitivity and specificity were 88.8% and 88.4%, respectively. We conclude that the MSPS is a simple screening tool for predicting uncomplicated falciparum malaria patients turning to severe malaria. However, the MSPS may need revalidation in different geographical areas before utilized at specific places.