Specific Versus Empirical Anthelminthic Treatment in Eosinophilia

Prince of Songkla University

Status: Enrolling

Conditions: Eosinophilia

Treatments: Drug: Albendazole; Drug: Ivermectin or albendazole

Study type: Interventional

Funder types: Other

Identifiers

NCT06265870

Parasite in Eosinophilia

Details and patient eligibility

About

There are a few guidelines recommend about management of eosinophilia worldwide, most of guielines recommend a thorough history-taking and physical examination. Subsequently, investigations are requested based on suspected causes. In cases where parasite infection is suspected, particularly in developing countries, stool microscopy and serology are recommended. However, limitations such as low sensitivity of stool microscopy, the inconvenience of collecting multiple stool samples, and the high cost and unavailability of serology may arise. Consequently, some physicians opt for empiric anthelminthic regimens in managing eosinophilic patients, even without stool tests or if stool test results are normal. If subsequent complete blood count (CBC) results show a recovery of absolute eosinophil count, it is assumed that eosinophilia was caused by a parasite infection. While some studies demonstrate the efficacy and simplicity of this approach, there is a risk of overestimating parasite infection in eosinophilic patients, potential adverse drug reactions from unnecessary anthelminthic treatment, and the possibility of drug resistance due to inappropriate dosing. To address this gap, no study has yet compared the efficacy between specific anthelminthic treatment based on test results and empirical anthelminthic treatment in eosinophilic patients. Therefore, the investigators are conducting this study.

Full description

Eosinophilia is defined as an absolute eosinophil count exceeding 500 cells per microliter, calculated by multiplying the white blood cell count by the percentage of eosinophils.

Cause of eosinophilia vary from mild to life-threatening disease. Prevalence of each cause of eosinophilia vary on study population, the most common etiology in developing country is parasite infection.

Stool microscopy can be conducted using various methods. The Kato-Katz technique, recommended by the WHO, exhibits a sensitivity of only 52.4 percent (95%CI = 47.6 - 57.1 percent). More sensitive methods for parasite detection in stool, such as stool culture or PCR, are not readily available and can be costly. In the intervention group of this study, the investigators employed three different parasite detection methods (stool microscopy, stool culture, and PCR) to enhance sensitivity in detecting parasites.

Enrollment: 700 estimated patients

Sex: All

Ages: 18+ years old

Volunteers: No Healthy Volunteers

Inclusion criteria

• Participants who come for check-ups at general practitioner, primary care unit, and Srivejchavat Premium Center have an absolute eosinophil count greater than 500 cells/microliter with a white blood cell count less than 10,000 cells/microliter.
• Age at least 18 years old
• Consent to participate in research

Exclusion criteria

• Having any characteristics that need urgent care 1.1 Having history of unintended significant weight loss is defined as the loss of body weight exceeding 10% within a span of six months without deliberate attention.

1.2 Physical examination revealed a body temperature equal to or greater than 37.8 degrees Celsius, lymphadenopathy or hepatosplenomegaly.

1.3 CBC revealed blast cell

• Receiving anthelminthic drug within 6 months
• Underlying cancer (active stage), HIV, HBV, HCV, collagen vascular disease, active TB
• Allergy to albendazole, ivermectin, or metronidazole
• Pregnancy or lactation
• Serum transaminase higher than 2 times of upper normal limit
• Taking medications that may induce eosinophilia within the past three months, such as herbal supplements, NSAIDs, Salicylic acid, Carbamazepine, Colchicine, Nitrofurantoin, Dapsone, or Minocycline, was reported.

Trial design

Primary purpose: Treatment

Allocation: Randomized

Interventional model: Parallel Assignment

Masking: None (Open label)

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700 participants in 2 patient groups, including a placebo group

Specific anthelminthic

Active Comparator group

Description:

Participants were asked to provide stool samples for three consecutive days for testing through microscopy, culture, and PCR to detect parasites. * This study will combine wet smear and Kato's thick smear methods, with duplicate samples collected from each stool specimen to maximize parasite detection. To ensure reliability, two experienced microscopists will independently examine all four slides, and an independent report generated. In cases of discrepant results, a third microscopist will arbitrate, and the final diagnosis determined by majority vote. * Stool culture will look for Strongyloides stercoralis and hookworm larvae. * Stool PCR: Targeted gene of 7 helminths will be amplified and detected by multiplex real-time PCR. The reaction will be dividing into three assays. Following the analysis of the stool samples, participants will receive specific anthelminthic treatment tailored to the results of the stool tests.

Treatment:

Drug: Ivermectin or albendazole

Empirical anthelminthic

Placebo Comparator group

Description:

Participants will receive an empirical anthelminthic regimen consisting of albendazole 400 mg twice a day for seven consecutive days. Following this treatment, a follow-up complete blood count (CBC) will be requested to assess responsiveness.

Treatment:

Drug: Albendazole