Helminthosis and eosinophilia in Spain (1990-2015)

Case Report: Hymenolepis diminuta in an asymptomatic Ecuadorian child

Background

The cestode Hymenolepis diminuta is a cosmopolitan parasite, which in the adult stage is usually found in the small intestine of rats and accidentally in humans.

Case report

We describe the finding of eggs of this parasite in an asymptomatic 3-year-old child. The child had extremely high IgE values of 1,376 IU/ml. After receiving treatment with Albendazole suspension 400mg/20mL, on the 10th day post-treatment, he showed no H. diminuta eggs in his fecal matter.

Conclusions

Detailed morphological review of Hymenolepis nana-like eggs is recommended to distinguish them from H. diminuta eggs.

A 14-year review (2007-2020) of helminthiasis epidemiology in a hospital in Southern Madrid, Spain

PURPOSE

Vast majority of helminth diseases remain neglected tropical diseases (NTDs), causing significant morbidity. The widespread and periodic distribution of antiparasitic drugs, remains the cornerstone for controlling these diseases. In Spain, most helminthiasis cases are imported, and suspicion and diagnosis have become increasingly important. Our primary objective is to present the epidemiological landscape of helminthiasis diagnoses within our facility, while also detailing the demographic characteristics of the affected population.

METHODS

A retrospective study was conducted at the Hospital Universitario Severo Ochoa (HUSO) from January 1, 2007, to December 31, 2020, encompassing all diagnosed cases of helminthiasis during this period. Comprehensive epidemiological, clinical, and microbiological data were gathered for all diagnosed patients. The study population comprised patients receiving treatment at the HUSO, as well as those receiving treatment at the Leganés and Fuenlabrada Primary Care Units. Subsequently, descriptive and comparative statistics were performed, comparing Spanish and foreign patients.

RESULTS

During this period, a total of 952 patients were diagnosed with some form of helminthiasis. Among them, 495 were Spanish, and 457 were foreign. The total number of helminths identified, including patients with multiple infections, was 1,010. Significant differences were observed between Africans and Americans in terms of age distribution, with a higher prevalence among Africans in the 0-15 age range and among Americans in the 31-60 age range. Variations were noted in the distribution of helminths, with S. stercoralis significantly affecting Americans. For Spanish patients, the presence of Trichuris trichiura and S. stercoralis was significantly associated with eosinophilia, whereas among foreign patients, it was associated with Trichuris trichiura, Ascaris lumbricoides among others. Regarding symptoms, skin manifestations were more frequent among Spanish, while digestive were more common among foreigners.

CONCLUSIONS

This study offers crucial epidemiological insights into helminth infections observed over time in a Madrid hospital. Although the prevalence of helminth infections has been decreasing, there is still a need for screening and diagnosing foreign patients.

Executive summary consensus statement of imported diseases group (GEPI) of the Spanish Society of Infectious Diseases and Clinical Microbiology (SEIMC) and the Spanish Society of Tropical Medicine and International Health (SETMSI), on the diagnostic and treatment of imported schistosomiasis

Schistosomiasis is a highly prevalent disease, especially in immigrant populations, and is associated with significant morbidity and diagnostic delays outside endemic areas. For these reasons, the Spanish Society of Infectious Diseases and Clinical Microbiology (SEIMC) and the Spanish Society of Tropical Medicine and International Health (SEMTSI) have developed a joint consensus document to serve as a guide for the screening, diagnosis and treatment of this disease outside endemic areas. A panel of experts from both societies identified the main questions to be answered and developed recommendations based on the scientific evidence available at the time. The document was reviewed by the members from both societies for final approval.

Study of the Use of Antinematode Drugs, Mebendazole and Pyrantel, in Galicia (Spain) from 2016 to 2020

To the best of our knowledge, there is no study on the use of drugs focused on the consumption of antinematode drugs in any region of the world. In the present study, we analyzed and evaluated the use of mebendazole and pyrantel in the provinces of Galicia (Spain), as well as described the variability of the consumption of both drugs between these provinces from 2016 to 2020. A descriptive, cross-sectional, and retrospective study of the consumption of these drugs, expressed in defined daily dose per 1000 inhabitants per day (DHD), was carried out. The DHD values for both drugs were small, although clearly higher, both on average and in variability, in the case of mebendazole. The difference in the mean DHD between both drugs and the geographical differences observed was statistically significant. The seasonal differences were statistically significant for both active principles, with lower values in summer. The active principle most consumed in all the provinces and years was mebendazole. The main consequence of the excessive use of this drug compared to pyrantel may be the increased risk of the development of resistance and of therapeutic failure, as well as the consequent limitation of pharmacological options in the future.

Toxocariasis in migrant children: A 6 years' experience in a reference pediatric unit in Spain

BACKGROUND

Toxocariasis is a worldwide distributed zoonosis that affects characteristically children. Clinical presentation is highly variable, often asymptomatic, and treatment duration is controversial.

METHODS

A retrospective descriptive study (January 2014-December 2019) was performed in a referral Unit for Pediatric Tropical Diseases. Patients younger than 18 years of age diagnosed with toxocariasis were included.

RESULTS

Out of 931 children screened for toxocariasis, 49 (5.3%) were seropositive. The median age was 11.0 years, 55.1% male and 30.6% referred contact with puppies. Overall, 34.7% were Latin-American, 24.5% Asiatic, 20.4% European, and 20.4% African. Only 34.7% presented symptoms, gastrointestinal the most common (52.9%). The 57.1% of children presented eosinophilia and 50% elevated total IgE. Most cases (95.9%) corresponded to covert toxocariasis. All children were treated with albendazole for 5-14-21 days, and 4 children required a second course. Follow-up data were available in 32 children (65.3%) for a median of 7 months, showing a progressive decline in eosinophils, IgE-titers and ELISA optical density.

CONCLUSION

Toxocariasis is mostly asymptomatic in children and eosinophilia is not always present. Serological tests should be included in migrant health screening and in the diagnostic assessment of eosinophilia. Eosinophil count, IgE-titers and ELISA optical-density could be useful during follow-up.

Strong-LAMP Assay Based on a Strongyloides spp.-Derived Partial Sequence in the 18S rRNA as Potential Biomarker for Strongyloidiasis Diagnosis in Human Urine Samples

Human strongyloidiasis a soil-transmitted infection caused by Strongyloides stercoralis is one of the most neglected amongst the so-called Neglected Tropical Diseases (NTDs). S. stercoralis is a nematode, which is distributed worldwide; it has been estimated that it could affect millions of people, mainly in tropical and subtropical endemic regions. The difficulties of diagnosis lead to infection rates being underreported. Asymptomatic patients have chronic infections that can lead to severe hyperinfection syndrome or disseminated strongyloidiasis in immunocompromised patients. Strongyloidiasis can easily be misdiagnosed because conventional faecal-based techniques lack of sensitivity for the morphological identification of infective larvae in faeces. None of the currently used molecular methods have used urine samples as an alternative to faecal samples for diagnosing strongyloidiasis. This study was thus aimed at comparing, for the first time, the use of a new loop-mediated isothermal amplification (LAMP) molecular assay (Strong-LAMP) to traditional methods on patients' urine samples. Twenty-four urine samples were taken from patients included in a study involving two Spanish hospitals for strongyloidiasis screening using parasitological and serological tests. Strongyloides larvae were found in 11 patients' faecal samples, thereby ascertaining that they had the disease. Other patients had high antibody titres but no larvae were found in their faeces. All urine samples were analysed by PCR and Strong-LAMP assay. No amplification occurred when using PCR. Strong-LAMP led to detecting S. stercoralis DNA in urine samples from patients having previously confirmed strongyloidiasis by parasitological tests and/or a suspicion of being infected by serological ones. The Strong-LAMP assay is a useful molecular tool for research regarding strongyloidiasis in human urine samples. After further validation, the Strong-LAMP assay could also be used for complementary and effective diagnosis of strongyloidiasis in a clinical setting.

Seeking the reuse of effluents and sludge from conventional wastewater treatment plants: Analysis of the presence of intestinal protozoa and nematode eggs

Some of the microorganisms present in urban wastewater, which include intestinal protozoa and nematodes, can be pathogenic. Their (oo)cyst and egg transmissible stages are very resistant to environmental stresses and disinfectants and they are therefore difficult to remove. Thus, they can constitute a health risk if water or sludge obtained in the purification of wastewater is reused for agricultural purposes. In this context, the presence of intestinal protozoa and nematodes were studied in influents, effluents and sludge from five wastewater treatment plants (WWTPs) in the north of Spain by optical microscopy and PCR techniques. The removal efficiency of different wastewater treatments was also compared. The presence of protozoa has increased among the population discharging waste to WWTPs in recent years. Cryptosporidium spp., Giardia duodenalis, Entamoeba spp. and nematodes were detected in all of the WWTPs. Indeed, this is the first report of Entamoeba histolytica and Entamoeba moshkovskii in Spanish WWTPs. The water treatments studied showed different removal efficiencies for each species of intestinal protozoa, with the aerated lagoons providing the best results. (Oo)cysts were also detected in sludge even after aerobic digestion and dehydration. To avoid risks, (oo)cyst viability should be analysed whenever the sludge is to be used as a fertilizer. This study reinforces the necessity of establishing legal limits on the presence of protozoa in WWTP effluents and sludges, especially if reuse is planned. Further studies are necessary for a better understanding of the presence and behaviour of intestinal parasites.

Surveillance of strongyloidiasis in Spanish in-patients (1998-2014)

Background

Strongyloides stercoralis is a parasite that causes strongyloidiasis, a neglected tropical disease. S. stercoralis is a soil-transmitted helminth that is widely distributed in tropical and subtropical regions of the world. Strongyloidiasis can occur without any symptoms or as a chronic infection characterized by mild, unspecific symptoms such as pruritus, abdominal pain or discomfort; respiratory impairment also may manifest as a potentially fatal hyperinfection or disseminated infection. Most studies on strongyloidiasis in Spain have been related to chronic forms in immigrants or travellers from endemic zones and have mainly analysed out-patient populations. Studies of the impact of strongyloidiasis cases admitted to hospitals in Spain are lacking. Therefore, the aim of this study was to analyse the impact of strongyloidiasis in hospital care in Spain.

Methodology

We designed a retrospective descriptive study using the Minimum Basic Data Set (MBDS, CMBD in Spanish) for inpatients with ICD-9: 127.2 (strongyloidiasis) diagnoses admitted to hospitals in the Spanish National Health System between 1998 and 2014.

Principal findings

A total of 507 hospitalizations with diagnosis of strongyloidiasis were recorded, 324 cases (63.9%) were males. The mean (±SD) age was 42.1±20.1 years. The impact of strongyloidiasis on the total population of Spain was 0.06 cases per 10⁵ person-years, and the infection burden increased progressively over time (from 0.01 cases per 10⁵ person-years in 1999 to 0.10 cases per 10⁵ person-years in 2014). 40 cases (7.9%) died. The total cost was approximately €8,681,062.3, and the mean cost per patient was €17,122.4±97,968.8.

Conclusions

Our data suggest that strongyloidiasis is frequent in Spain and is increasing in incidence. Therefore, it would be desirable to improve the oversight and surveillance of this condition. Due to the fact that strongyloidiasis can be fatal, we believe that there is a need to establish risk categories for inclusion in national guidelines/protocols for screening individuals at risk of developing strongyloidiasis.

[Clinical approach to imported eosinophilia]

Eosinophilia is a common finding in international travelers and immigrants, being an helmintic infection its main etiology. The positive predictive value of eosinophilia for an helmintosis is low in travellers. Eosinophilia may be an incidental finding, or symptomatic, and it represents a clinical challenge due to the low sensitivity and specificity of direct and indirect parasitological diagnostic tests, respectively. It requires a structured approach based on geographical areas, environmental exposures and behavioral risks, and associated symptoms. The initial assessment should include a comprehensive and tailored anamnesis and physical examination, basic laboratory tests, a complete parasitological examination of stool samples and a Strongyloides stercoralis serology, supplemented with other explorations guided by epidemiological and clinical suspicion. Empiric treatment with albendazole and/or ivermectin (plus praziquantel if risk of schistosomiasis) is an option for unidentified persistent eosinophilia after study, and in persons in whom a proper assessment or follow-up can not be assured. In patients at risk for estrongiloidosis who are candidates for immunosuppressive therapies, it is indicated a prior screening and treatment to prevent a future hyperinfestation syndrome.