The positive diagnosis of ascaridiasis is sometimes difficult to identify because the anamnesis is insufficient, the clinical symptoms are poor or not very specific and the paraclinical arguments can be distinguished only in some cases and at different stages of the disease. Furthermore, the coproparasitological examination can ascertain negative results on false basis. Since the specialised literature associates ascaridiasis with peripheral eosinophilia, we attempted to monitor the frequency and the grade of this haematological parameter and its variations when considering the patients sex and age, in order to evaluate its diagnostic value.