European Journal of Cardiovascular Medicine

Hydatid disease, also known as cystic echinococcosis, is a parasitic zoonotic infection caused primarily by the larval stage of Echinococcus granulosus. It is an important public health concern, particularly in developing countries with a high prevalence of animal husbandry, close human-animal contact, and poor sanitation practices. The disease is transmitted via ingestion of eggs excreted in the faeces of infected canines, with humans acting as accidental intermediate hosts [1,2].

Endemic in many parts of the Middle East, South America, Africa, and Asia—including India—hydatid disease has significant clinical relevance due to its potential to involve multiple organs, most commonly the liver and lungs [3]. The condition often remains asymptomatic for years, with cysts growing slowly and presenting with non-specific symptoms such as abdominal pain, hepatomegaly, or respiratory complaints depending on the site of involvement [4]. Unusual sites such as the kidneys, spleen, ovaries, or even muscle tissues are less frequent but clinically challenging [5].

India has a variable regional prevalence of hydatid disease, influenced by cultural practices, veterinary health infrastructure, and environmental factors. However, limited data exist from tribal and underserved areas such as Surguja district in Chhattisgarh. Accurate local epidemiological data are essential to guide public health interventions, diagnostic vigilance, and preventive efforts such as deworming of domestic animals and community awareness [6,9].

This study was conducted to evaluate the prevalence, organ distribution, clinical profile, and associated risk factors of hydatid disease among patients presenting to a tertiary care centre in Surguja, Chhattisgarh. The study also aimed to assess diagnostic modalities used and their frequency, and explore associations between socio-demographic variables and organ involvement.

Study Design and Setting

This was a hospital-based cross-sectional study conducted in the Department of General Surgery at Mata Rajmohani Devi Memorial Hospital, associated with RSDKS Government Medical College, Ambikapur, Surguja, Chhattisgarh. The study was carried out over a period of 18 months, from October 2022 to March 2024.

Study Population

A total of 35 patients diagnosed with hydatid disease were included in the study. These patients presented to the surgery outpatient department or were admitted with radiologically or histologically confirmed hydatid cysts. All age groups and both sexes were included.

Inclusion Criteria

• Patients with a confirmed diagnosis of hydatid disease based on clinical presentation, imaging (USG, CT, MRI), or intraoperative findings.
• Patients providing informed consent for participation.

Exclusion Criteria

• Patients unwilling to provide consent.
• Cases with unconfirmed diagnoses or other cystic lesions of different etiology.

Data Collection and Variables Assessed

Patient data were collected using a structured proforma. Variables recorded included:

• Demographic details: age, sex, residence, dietary habits, socioeconomic status
• Exposure history: contact with dogs (domestic/street)
• Clinical presentation: symptoms, site of cyst
• Radiological investigations: ultrasonography, CT, MRI
• Operative findings and histopathological confirmation where applicable

Organ involvement (liver, lung, kidney, etc.) and associated clinical features were noted. Socio-demographic patterns were assessed for correlation with disease burden and organ involvement.

Statistical Analysis

Data were entered into Microsoft Excel and analyzed using standard statistical software. Descriptive statistics were expressed as mean ± standard deviation for continuous variables and percentages for categorical variables. Chi-square test and unpaired t-test were used to assess associations between categorical and continuous variables, respectively. A p-value < 0.05 was considered statistically significant.

1. Demographic and Baseline Characteristics

A total of 35 patients diagnosed with hydatid disease were included in the study. The mean age of the study population was 41.86 ± 18.17 years, with a slight female predominance—19 patients (54.3%) were female and 16 (45.7%) were male. The majority of patients (80%) resided in rural areas, while only 20% were from urban settings. Socioeconomic classification revealed that 42.8% of patients belonged to the lower middle class, followed by 28.6% in the lower-class category. These findings highlight the rural and socioeconomically disadvantaged profile of the affected population, underscoring the potential role of environmental and occupational exposure in disease transmission.

Table 1: Baseline Demographic Characteristics

2. Exposure History and Risk Factors

Among the 35 patients, the majority reported a mixed diet (94.3%), while only 5.7% were vegetarian. In terms of dog exposure—a known risk factor for hydatid disease—18 patients (51.4%) had frequent contact with street dogs, and 17 (48.6%) reported owning or handling domestic dogs. Most patients (80%) were from rural settings, aligning with higher environmental exposure to parasite reservoirs in livestock and dogs. No statistically significant association was observed between residence and dietary habits (p = 0.466), or between dog contact and residence (p = 0.802), suggesting widespread exposure risks across both environments.

Table 2: Exposure History and Risk Factors

 Figure 1. Distribution of Dog Contact Type Among Patients

Bar chart illustrating the proportion of patients with hydatid disease who reported contact with street dogs (51.4%) versus domestic dogs (48.6%). Contact with dogs—particularly strays—remains a key risk factor in transmission.

3. Clinical Presentation

The most common presenting symptom among patients with hydatid disease was abdominal pain, reported in 40% of cases. Hepatomegaly was the next most frequent finding, observed in 54.3% of patients on clinical examination. Other notable symptoms included fever, nausea, and a palpable mass. The clinical manifestations varied depending on the location and size of the hydatid cyst. Table 3 outlines the distribution of the most frequent symptoms reported at presentation.

Table 3: Frequency of Clinical Features

Figure 2. Most Common Clinical Presentations in Hydatid Disease

4. Organ Involvement

The liver was the most frequently involved organ, accounting for 74.29% of cases, with the right lobe being the most commonly affected subsite. Lung involvement was observed in 5.7% of cases. Rare sites of hydatid cyst localization included the kidney, ovary, peritoneum, bladder, spleen, and intramuscular tissues, each accounting for approximately 2.9% of cases. Table 4 summarizes the organ distribution of hydatid cysts in the study population.

Table 4: Organ Distribution in Hydatid Disease

5. Diagnostic Modalities

Ultrasonography (USG) was the most frequently employed diagnostic modality, used in 57.1% of cases. Computed Tomography (CT) scans were performed in 40% of patients, offering detailed anatomical information especially in complex or atypical cases. Magnetic Resonance Imaging (MRI) was used sparingly, seen in only one patient (2.9%) for evaluation of cysts in rare sites. Table 5 summarizes the distribution of imaging modalities used for diagnosis in this study.

Table 5: Diagnostic Modalities Used in Hydatid Disease

6. Statistical Comparisons

Statistical comparisons were performed to explore associations between risk factors and demographic variables. No statistically significant association was found between dietary habits and place of residence (p = 0.466), or between contact with dogs and residence (p = 0.802). Similarly, no significant association was observed between the organ involved and gender (p = 0.275), nor between contact with dogs and gender (p = 0.511). An unpaired t-test comparing mean age between male and female patients showed no significant difference (t = 0.1848, p = 0.8546). These results suggest that demographic characteristics were not strongly associated with exposure risk or organ localization in this cohort.

Table 6: Summary of Statistical Tests

7. Prevalence Summary

Based on hospital records and population estimates, the overall prevalence of hydatid disease in the study area was calculated at 1.48 cases per 100,000 population. The prevalence varied by area of residence: urban areas had a prevalence of 2.88 per 100,000, while rural areas showed a slightly lower rate at 1.32 per 100,000. Although the prevalence appeared numerically higher in urban regions, the small sample size and limited geographic scope of the study limit definitive conclusions. These figures highlight the continued presence of hydatid disease in both urban and rural settings of Chhattisgarh.

Hydatid disease is a significant public health concern in many developing countries, including India, due to widespread animal-human contact, inadequate veterinary controls, and limited public health awareness [10,11]. In our study, hydatid cysts most commonly involved the liver (74.29%), particularly the right lobe, consistent with global findings that identify the liver as the primary site of cyst deposition following hematogenous spread via the portal system [12–14]. This trend aligns with Gharbi et al.'s classic imaging classification of hepatic hydatid cysts, which remains central to radiological assessment [10].

While liver involvement dominates, extrahepatic manifestations—though rare—carry diagnostic and therapeutic challenges. We observed pulmonary involvement in 5.7% of patients, which is within the expected range for lung hydatidosis (8.5–43%) and mirrors patterns reported by Tor et al. and Cangiotti et al. [12,16]. Rare sites such as the kidney, peritoneum, spleen, and even intramuscular areas (each 2.9%) underscore the disseminating potential of Echinococcus granulosus larvae and have been documented in surgical series from Iraq, Iran, and North Africa [14,15,17–20].

These rare sites often lead to delayed diagnosis due to nonspecific symptoms and unfamiliarity among clinicians. Gossios et al. and Beggs et al. emphasized that CT and MRI are instrumental in identifying unusual cyst locations, which might otherwise be missed or misdiagnosed [21,22]. In our study, ultrasonography was the most used modality (57.1%), while CT (40%) and MRI (2.9%) were reserved for atypical or inaccessible sites—similar to practices described by Haliloğlu et al. and Zlitni et al. [23,24].

Demographically, most patients were from rural areas (80%) and belonged to lower or lower-middle socioeconomic classes. This is in line with reports from other Indian and international studies where hydatidosis is more prevalent in rural populations due to occupational exposure, poor sanitation, and frequent contact with stray or domesticated dogs [11,14]. Although over 50% of our patients reported contact with dogs and the vast majority consumed a mixed diet, we found no statistically significant association between these factors and hydatid disease. This suggests widespread baseline exposure in endemic regions, aligning with previous findings from Barwari et al. and Paniker [11,14].

Clinically, abdominal pain and hepatomegaly were the leading symptoms, reflecting hepatic involvement, while fever and palpable masses were also observed. These are classical but nonspecific symptoms often seen in hepatic hydatidosis and reported in prior surgical reviews [19,20].

Our prevalence estimate of 1.48 cases per 100,000 population in Surguja is consistent with Indian data suggesting variable incidence across regions (1–200 per 100,000) [14]. Interestingly, our data showed slightly higher prevalence in urban areas, possibly reflecting referral bias or better access to diagnostic imaging, rather than a true epidemiologic difference.

This study reinforces the importance of awareness among clinicians and the public, particularly in endemic zones, regarding the zoonotic potential and multisystem presentation of hydatid disease. Improved access to imaging, early surgical intervention, and integrated one-health approaches involving veterinary surveillance are necessary to reduce the disease burden [10,13,18].

Limitations

This study was limited by its small sample size, which may reduce the generalizability of findings. Being a single-centre study conducted in a tertiary care hospital, it may be subject to referral bias and may not fully represent the community prevalence of hydatid disease. Additionally, serological testing, which can aid diagnosis in ambiguous cases, was not performed in all patients due to logistical constraints. Finally, the cross-sectional design precludes evaluation of long-term outcomes or treatment efficacy.

Hydatid disease continues to be an endemic parasitic infection in rural and underserved regions such as northern Chhattisgarh. The liver remains the most frequently involved organ, and contact with dogs—particularly in rural settings—continues to be a primary risk factor. Although imaging modalities like ultrasonography and CT remain reliable for diagnosis, awareness among healthcare professionals and communities remains essential. Preventive strategies, including dog deworming, health education, and improved sanitation, are crucial to reducing the burden of this preventable disease.

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