Surgical Burden and Centralisation of Hepatic Cystic and Alveolar Echinococcosis Management in Kazakhstan: A Nationwide Administrative Data Analysis (2023–2025)

Highlights

Public health relevance—How does this work relate to a public health issue?

• Kazakhstan has one of the highest reported incidences of hepatic echinococcosis worldwide, yet the national surgical burden of cystic and alveolar disease had not previously been quantified using administrative health data.
• This study links national health insurance records (GOBMP/OSHI) with single institutional surgical data to describe how cystic and alveolar echinococcosis are managed across Kazakhstan.

Public health significance—Why is this work of significance to public health?

• National surgical volume for hepatic echinococcosis increased over the three-year study period, driven by a rising share of the more aggressive alveolar form.
• Surgical management of alveolar echinococcosis is highly concentrated in two tertiary centres (Astana and Almaty), revealing marked geographic disparities in access to specialised hepatobiliary care.

Public health implications—What are the key implications or messages for practitioners, policy makers and/or researchers in public health?

• These findings support the development of a national echinococcosis registry to enable systematic surveillance and long-term monitoring of surgical outcomes.
• Establishing formal referral networks for complex hepatobiliary parasitic disease could improve equitable, timely access to specialised surgical care across all regions of Kazakhstan.

Abstract

Background: Kazakhstan is among the most highly endemic countries for hepatic echinococcosis worldwide, yet no study systematically characterised the national hepatobiliary surgical burden of cystic (CE) and alveolar (AE) echinococcosis using administrative health data. Methods: National operative data from the Guaranteed Volume of Free Medical Care (GOBMP) and Compulsory Social Health Insurance (OSHI) Systems (1 January 2023–31 December 2025) were combined with institutional case series from the National Research Oncology Center (NROC), Astana (2021–2025). Cases were identified using ICD-10 diagnosis codes and ICD-9-CM procedure codes. Regional and species-specific differences in surgical approach were assessed using Pearson’s chi-square test; continuous variables were compared using the Mann–Whitney U test. Results: A total of 143 hepatic echinococcosis surgeries were performed nationally over the three-year period, with a 12.8% increase in annual volume (47 in 2023, 43 in 2024, 53 in 2025), though this year-to-year variation was not statistically significant (χ² = 1.06, df = 2, p = 0.59). CE accounted for 74.8% of cases (n = 107), AE for 18.9% (n = 27), and unspecified hepatic echinococcosis for 6.3% (n = 9); the proportion of AE rose from 17.0% in 2023 to 26.4% in 2025. Astana performed 46.2% of all operations nationally, with its share increasing from 34.0% to 58.5% over the study period; together with Almaty, it accounted for 92.6% of all AE cases. Partial hepatic resection was the predominant procedure overall (81.1%), while AE was managed exclusively by resectional or lobar procedures (χ² = 15.37, p = 0.004), with no percutaneous approaches used. In the NROC case series (n = 63), AE patients were older (median 43.5 vs. 33 years, p = 0.036) and had longer postoperative hospital stays (median 12 vs. 10 days, p = 0.015) than CE patients. Conclusions: Surgical management of hepatic echinococcosis in Kazakhstan is increasingly centralised in Astana and Almaty, with AE consistently requiring more extensive resectional surgery and greater healthcare resource use than CE. These findings support the development of a national echinococcosis registry and formal referral pathways to guide resource allocation and surgical planning.

1. Introduction

Liver parasitic cysts, caused by Echinococcus granulosus or Echinococcus multilocularis, represent a zoonotic disease of substantial public health relevance [1]. Humans are accidental intermediate hosts, and hepatic localisation accounts for more than two-thirds of all cases. The two species produce clinically distinct entities: cystic echinococcosis (CE), which forms slow-growing, well-encapsulated cysts, and alveolar echinococcosis (AE), which exhibits an infiltrative, tumour-like growth pattern associated with substantially higher morbidity and mortality.

Both species follow a two-host life cycle involving definitive and intermediate hosts. Dogs and other canids serve as definitive hosts, harbouring the adult tapeworm in the small intestine, while various herbivores act as intermediate hosts, developing larval (metacestode) cysts after ingesting eggs shed in canid faeces. In Kazakhstan, as in much of Central Asia, sheep are the principal intermediate host for E. granulosus, reflecting the region’s pastoral farming traditions; in other endemic settings elsewhere in the world, cattle, goats, or camels may instead serve as the predominant intermediate host. Small rodents act as the natural intermediate host for E. multilocularis, with foxes as the principal definitive host [2]. Humans become infected incidentally through ingestion of eggs from contaminated food or water, or through direct contact with infected canids, and do not participate in the natural transmission cycle.

According to modelled estimates from the Global Burden of Disease study, in 2019 Central Asia had among the highest estimated incidence rates of cystic echinococcosis (CE) per 100 000 population globally, comparable to or exceeding those reported for Eastern Europe and North Africa; within this modelling framework, Kazakhstan was estimated to have the highest age-standardised incidence rate (ASIR) among Central Asian countries (ASIR = 127.56), followed by Uzbekistan (123.53), Tajikistan (121.8) and Kyrgyzstan (95.61). Over the study period, the incidence of CE in the global population transitioned from a single peak (45–74 years) to two peaks (15–34 years and 45–69 years), with peak incidence of 4.09 (55–59 years) and 3.45 (20–24 years) per 100 000 population. These modelled estimates, while subject to the inherent uncertainty of burden-of-disease projections, indicate that CE represents an important public health problem in Central Asia and in Kazakhstan in particular [3,4]. Population-level epidemiological data specific to AE remain considerably more limited in Kazakhstan than for CE; the estimates above therefore predominantly reflect the burden of CE.

Kazakhstan is a Central Asian country with long-standing agrarian traditions, where sheep breeding remains widely practiced in rural areas. Based on local veterinary studies, an estimated 30 to 50% of sheep in endemic regions are infected with hydatid cysts [5]. Local statistical data report a stable human incidence of approximately 800–1000 surgically or medically treated cases annually nationwide, a figure that has remained largely unchanged since the sharp post-Soviet rise reported during the 1990s [5].

However, this widely cited national incidence figure is now over a decade old, and it does not capture the clinical or surgical burden of disease. More recent national-level studies have begun to address aspects of this gap: a nationwide retrospective analysis of surgically treated echinococcosis in Kazakhstan (2017–2024) reported declining case rates alongside marked regional disparities [6], and a separate study estimated national incidence rates of surgically managed cystic echinococcosis for 2007–2016 [7]. However, neither study specifically characterised the surgical approach, species-level distribution, or centre-level concentration of hepatobiliary surgical care. Most available epidemiological data for Kazakhstan are derived from single-centre case series or from global modelling studies such as the Global Burden of Disease project, which rely on statistical estimation rather than direct clinical or administrative records and therefore cannot inform health system planning, resource allocation, or surgical practice at the national level. To date, no study has systematically characterised the surgical burden of hepatic echinococcosis, by species and surgical approach, using nationwide administrative health data in Kazakhstan.

Given the persistently high prevalence of human CE and AE in Kazakhstan and the absence of updated, granular national data on surgical management, this study aimed to characterise the surgical burden of hepatic echinococcosis in Kazakhstan using data from the national administrative healthcare database.

2. Materials and Methods

2.1. Data Sources

Kazakhstan is considered endemic for echinococcosis across its entire territory, although disease burden is markedly heterogeneous by region: national surveillance data indicate that surgically treated case rates are highest in the southern and western regions of the country, while northern and eastern regions report substantially lower rates [6]. With a national population of approximately 20 million, complex hepatobiliary resections for echinococcosis are performed deliberately at three major tertiary hepatobiliary surgery centres—Astana, Almaty, and Karaganda—whereas in other regions surgical intervention is typically limited to incidental intraoperative findings or percutaneous/open drainage rather than planned major resection.

This study used two complementary data sources. First, national operative statistics were obtained from Kazakhstan’s national health information system, which records hospital admissions and procedures under two financing mechanisms: the Guaranteed Volume of Free Medical Care (GOBMP), which covers oncology-classified patients, and Compulsory Social Health Insurance (OSHI), which covers non-oncology patients. Because hepatic echinococcosis in Kazakhstan is managed within oncological surgical services (including at NROC, a national oncology centre), cases may be funded under either mechanism depending on administrative classification rather than underlying diagnosis; both funding streams were therefore combined into a single national dataset covering the period from 1 January 2023 to 31 December 2025 to ensure complete national case ascertainment. Second, a retrospective clinical case series was assembled from institutional surgical records of the National Research Oncology Center (NROC), Astana, covering patients undergoing surgery for hepatic echinococcosis between January 2021 and December 2025.

2.2. Case Identification

National-level cases were identified by International Classification of Diseases 10-th revision (ICD-10) [8] diagnosis codes B67.0, B67.3, B67.5, B67.7, and B67.8, combined with International Classification of Diseases 9-th revision (ICD-9) [9] operative codes 50.22 (partial hepatic resection), 50.29 (other procedures), and 50.30 (hepatic lobectomy). NROC case series patients were identified from institutional records with diagnosis confirmed by histopathology and/or intraoperative findings. In summary, a case was defined as any patient undergoing a resectional, lobar, or other destructive hepatic procedure with a concurrent diagnosis code for hepatic echinococcosis; this coding-based definition captures both symptomatic presentations and incidental intraoperative diagnoses made during surgery performed for other indications, provided the associated procedure and diagnosis codes were recorded. No incidental intraoperative diagnoses were identified in the NROC institutional series, where all patients had a preoperative diagnosis. Liver transplantation, coded separately (ICD-9-CM 50.5x), fell outside the scope of the present case-identification strategy and is addressed separately in the Discussion. The national dataset does not include a distinct code for reoperations; a patient undergoing repeat surgery (e.g., for recurrence) could therefore not be reliably distinguished from a new case at the national level, whereas repeat procedures were identifiable from clinical records in the NROC series.

2.3. Variables

For the national dataset, region, diagnosis code, operative code, and annual case volume were extracted. For the NROC case series, patient-level variables included age, sex, region of residence, diagnosis (cystic echinococcosis CE or alveolar echinococcosis AE), preoperative ELISA serology status, administration of preoperative antiparasitic therapy (albendazole), type of surgical procedure, and postoperative length of hospital stay.

2.4. Statistical Analysis

Descriptive statistics summarised case counts and proportions for the national dataset, with comparisons across years and regions performed using Pearson’s chi-square test. For the NROC case series continuous variables (age, length of stay) were summarised as median and interquartile range (IQR) given non-normal distribution and compared between AE and CE groups using the Mann–Whitney U test. Categorical variables were compared using Pearson’s chi-square test. A two-sided p-value < 0.05 was considered statistically significant. All analyses were performed in Stata (version 18, StataCorp, College Station, TX, USA).

2.5. Ethical Considerations

This study used aggregated, anonymized national administrative data and deidentified institutional case records. No patient-identifying information was accessed or reported. Ethical approval was exempted for the study given the retrospective anonymized nature of the data.

3. Results

A total of 143 hepatic echinococcosis operations were performed across Kazakhstan during the three-year study period. Annual surgical volume was 47 cases in 2023 (32.9%), 43 in 2024 (30.1%), and 53 in 2025 (37.1%), representing a net increase of 12.8% between 2023 and 2025, although this year-to-year variation was not statistically significant on a goodness-of-fit test against a uniform annual distribution (χ² = 1.06, df = 2, p = 0.59). A separate, complementary institutional case series of 63 patients was analysed from NROC (see below).

Species distribution. Cystic echinococcosis (CE; E. granulosus, B67.0/B67.3) accounted for the majority of cases across all years (74.8%; n = 107; 95% CI 67.1–81.2%). Alveolar echinococcosis (AE; E. multilocularis, B67.5/B67.7) comprised 18.9% of the total (n = 27; 95% CI 13.3–26.1%), while unspecified hepatic echinococcosis (B67.8) represented 6.3% (n = 9; 95% CI 3.3–11.5%; Wilson score intervals). Notably, the proportion of AE increased from 17.0% in 2023 to 11.6% in 2024, with a subsequent rise to 26.4% in 2025 (full annual breakdown in

Table 1. Annual distribution of hepatic echinococcosis operations by parasite species, Kazakhstan 2023–2025.

Year	AE n (%)	CE n (%)	Unspecified n (%)	Total (n)	p-Value
2023	8 (17)	37 (78.7)	2 (4.3)	47
2024	5 (11.6)	35 (81.4)	3 (7.0)	43
2025	14 (26.4)	35 (66.0)	4 (7.5)	53
Total	27 (18.9)	107 (74.8)	9 (6.3)	143	0.374

AE, alveolar echinococcosis (E. multilocularis, ICD-10 B67.5/B67.7); CE, cystic echinococcosis (E. granulosus, ICD-10 B67.0/B67.3). p value by the Pearson chi-square test.

).

Regional distribution. Astana was the dominant surgical centre throughout the study period, accounting for 46.2% of all operations (n = 66). Its share of national volume increased progressively from 34.0% in 2023 to 44.2% in 2024 and 58.5% in 2025. Almaty was the second largest contributor overall (16.8%; n = 24), followed by East Kazakhstan (11.9%; n = 17) and Karaganda (8.4%; n = 12). Shymkent contributed 18.6% of national volume in 2024 but declined markedly to 1.9% in 2025. Kostanay and West Kazakhstan each recorded a single case across the entire study period. The full annual regional breakdown is provided in Table S1 (Supplementary Material).

Surgical approach. Partial hepatic resection (ICD-9 50.22) was the predominant procedure overall (81.1%; n = 116). Its proportion varied from 78.7% in 2023 to 90.7% in 2024 and 75.5% in 2025. Other methods of hepatic destruction (50.29), including percutaneous approaches, accounted for 11.9% (n = 17), with an increase from 10.6% in 2023 to 17.0% in 2025. Lobectomy (50.30) was the least frequent procedure (7.0%; n = 10), declining from 10.6% in 2023 to 2.3% in 2024 before rising to 7.5% in 2025 (

Table 2. Annual distribution of hepatic echinococcosis operations by surgical approach, Kazakhstan 2023–2025.

Year	Partial Resection n (%)	Lobectomy n (%)	Other n (%)	Total (n)
2023	37 (78.7)	5 (10.6)	5 (10.6)	47
2024	39 (90.7)	1 (2.3)	3 (7.0)	43
2025	40 (75.5)	4 (7.5)	9 (17.0)	53
Total	116 (81.1)	10 (7.0)	17 (11.9)	143

Partial resection, ICD-9 50.22; Lobectomy, ICD-9 50.30; Other, ICD-9 50.29 (includes percutaneous procedures). p-value not reported for annual comparison (trend analysis not applicable to 3-year data).

).

Astana versus other regions. When comparing Astana to all other regions combined, a statistically significant difference in species distribution was observed (χ² = 8.15, df = 2, p = 0.017). Astana performed a higher proportion of AE cases (27.3%; 18/66) compared to other regions (11.7%; 9/77), consistent with centralisation of complex cases to a tertiary referral centre. A significant difference was also found in surgical approach (χ² = 9.55, df = 2, p = 0.008): other methods of destruction (50.29) were more frequently performed outside Astana (19.5%; 15/77) than in Astana (3.0%; 2/66), while resectional procedures predominated at the national centre (

Table 3. Comparison of type of echinococcosis distribution and surgical approach between Astana (capital) and other regions, Kazakhstan 2023–2025.

A. Type of Echinococcosis	AE n (%)	CE n (%)	Unspecified n (%)	Total (n)	p-Value
Astana	18 (27.3)	42 (63.6)	6 (9.1)	66
Other regions	9 (11.7)	65 (84.4)	3 (3.9)	77
Total	27 (18.9)	107 (74.8)	9 (6.3)	143	0.017
B. Surgical Approach	Partial Resection n (%)	Lobectomy n (%)	Other n (%)	Total (n)	p-Value
Astana	58 (87.9)	6 (9.1)	2 (3.0)	66
Other regions	58 (75.3)	4 (5.2)	15 (19.5)	77
Total	116 (81.1)	10 (7.0)	17 (11.9)	143	0.008

Partial resection, ICD-9 50.22; Lobectomy, ICD-9 50.30; Other, ICD-9 50.29 (includes percutaneous procedures). p-values by Pearson chi-square test. A: χ² = 8.15, df = 2. B: χ² = 9.55, df = 2.

).

Species and surgical approach. All AE cases were treated exclusively by resectional procedures—partial hepatic resection (77.8%; 21/27) or lobectomy (22.2%; 6/27)—with no percutaneous or destructive approaches recorded. In contrast, CE cases underwent partial resection in 81.3% (87/107), lobectomy in 3.7% (4/107), and other methods in 15.0% (16/107). A formal statistical test of this association was not performed, since destructive/percutaneous approaches do not form part of the AE treatment protocol, making a direct significance test across all three procedure categories of limited clinical interpretive value.

Regional concentration of alveolar echinococcosis. To further examine the distribution of AE cases, Almaty was compared to all other regions excluding Astana. Almaty demonstrated a significantly higher proportion of AE cases (29.2%; 7/24) compared to the remaining regions (3.8%; 2/53) (χ² = 11.23, df = 2, p = 0.004). Together, Astana and Almaty accounted for 25 of 27 AE cases (92.6%) nationally, indicating that surgical management of alveolar echinococcosis is effectively concentrated in these two urban tertiary centres.

To complement national administrative data with patient-level clinical detail, a case series of 63 patients undergoing surgery for hepatic echinococcosis at the National Research Oncology Center (NROC), Astana, between 2021 and 2025 was analysed. Of these, 49 (77.8%) had cystic echinococcosis (CE) and 14 (22.2%) had alveolar echinococcosis (AE).

Patients with AE were significantly older than those with CE (median age 43.5 vs. 33 years; Mann–Whitney p = 0.036) and experienced longer postoperative hospital stays (median 12 vs. 10 days; p = 0.015) (

Table 4. Patient characteristics by type of echinococcosis, National Research Oncology Center, Astana (2021–2025).

Characteristic	AE (n = 14)	CE (n = 49)	p-Value
Age, years, median (IQR)	43.5 (33–50.5)	33 (26–40)	0.036
Female se, n (%)	8 (57.1%)	28 (57.1%)	1.000
Length of stay, days, median (IQR)	12 (11–14)	10 (8–12)	0.015
Positive ELISA serology, n (%)	6 (42.9%)	19 (38.8%)	0.783
Preoperative antiparasitic therapy, n (%)	2 (14.3%)	10 (20.4%)	0.607

AE, alveolar echinococcosis; IQR, interquartile range. Age and length of stay compared using the Mann–Whitney U test (Wilcoxon rank-sum); categorical variables by the Pearson chi-square test.

). Sex distribution was identical between groups (57.1% female in both; p = 1.000). No significant difference was observed in preoperative ELISA seropositivity (42.9% AE vs. 38.8% CE; p = 0.783) or in administration of preoperative antiparasitic therapy (14.3% AE vs. 20.4% CE; p = 0.607).

Surgical approach differed markedly by species (

Table 5. Surgical approach by type of echinococcosis, National Research Oncology Center, Astana (2021–2025).

Type	Resection n (%)	Other n (%)	Lobectomy n (%)	Total n
AE	5 (35.7)	1 (7.1)	8 (57.1)	14
CE	26 (51.1)	21 (42.9)	2 (4.1)	49
Total	31 (49.2)	22 (34.9)	10 (15.9)	63

Resection, other methods, and lobectomy are mutually exclusive surgical categories, as defined in the Methods.

). Lobectomy was the predominant procedure for AE (57.1%; 8/14), whereas partial resection (53.1%; 26/49) and other methods (42.9%; 21/49) predominated for CE, with lobectomy performed in only 4.1% (2/49) of CE cases. A formal statistical comparison across the three procedure categories was not performed for this association, since destructive/percutaneous approaches do not form part of the AE treatment protocol, rendering such a comparison of limited interpretive value; the descriptive pattern nonetheless closely parallels that observed in the national administrative dataset (see Species and surgical approach, above), reinforcing that AE consistently requires more extensive resectional surgery.

4. Discussion

This study presents a three-year national analysis of surgical treatment of hepatic echinococcosis in Kazakhstan, based on administrative data from the GOBMP and OSHI systems. A total of 143 operations were performed between 2023 and 2025, with a net increase of 12.8% in annual surgical volume over the study period. These figures likely represent only a fraction of the true disease burden, given that Kazakhstan remains one of the highest-endemic countries for echinococcosis globally, with reported population-based ultrasound prevalence rates of cystic echinococcosis in humans in some regions of Kazakhstan (e.g., the Turkestan region) substantially exceeding the number of surgically treated cases nationally [10,11].

The proportion of alveolar echinococcosis increased from 17.0% in 2023 to 26.4% in 2025, although this trend did not reach statistical significance (χ² = 4.24, p = 0.374), likely reflecting the short observation window and relatively small absolute numbers. Nevertheless, the near-doubling of hepatobiliary surgery performed for AE in absolute terms between 2023 and 2025 warrants attention. Alveolar echinococcosis carries substantially higher morbidity and mortality than cystic echinococcosis due to its invasive, tumour-like behaviour and frequent requirement for extended hepatectomy or liver transplantation in advanced stages. Whether this increase reflects a genuine epidemiological shift, improved diagnostic awareness, or increased referral of complex cases to surgical centres cannot be determined from administrative data alone; however, all three explanations have meaningful implications for surgical planning and public health policy. A comparable rising trend in AE incidence has been documented across historically endemic and newly affected areas of Europe over recent decades, with two emerging epicentres identified in the Alpine and Baltic regions, suggesting that the increase observed in Kazakhstan may likewise reflect a genuine epidemiological shift rather than solely improved case ascertainment [12].

A key finding of this study is the progressive centralisation of surgical care in Astana, whose share of national operative volume rose from 34.0% in 2023 to 58.5% in 2025. Together, Astana and Almaty accounted for 92.6% of all AE cases nationally, and both centres demonstrated significantly higher proportions of AE compared to other regions (p = 0.017 and p = 0.004, respectively). This pattern is consistent with the known complexity of AE surgery, which typically requires advanced hepatobiliary expertise, intraoperative imaging, and multidisciplinary support not universally available at regional level. Centralisation of complex hepatic surgery to high-volume tertiary centres is associated with improved outcomes in other hepatobiliary conditions and likely confers similar benefits in AE management. This pattern mirrors international experience in AE-endemic countries: in France, clinical management and national surveillance of AE has for decades been coordinated through a single National Reference Centre connected to a network of affiliated regional units, enabling systematic case ascertainment, standardised multidisciplinary decision-making, and long-term outcome tracking [13]. A comparable formal referral-network model, rather than the currently informal centralisation observed in Astana and Almaty, may further improve case detection, treatment standardisation, and outcome monitoring for AE in Kazakhstan. Complex hepatobiliary resections for echinococcosis are performed deliberately at these tertiary centres, whereas surgical intervention elsewhere is typically limited to incidental findings or drainage procedures, consistent with the case-complexity pattern described in the Methods.

The association between species and surgical approach was statistically significant (χ² = 15.37, p = 0.004). No AE case was treated by percutaneous or destructive methods; all underwent formal hepatic resection or lobectomy. This is consistent with current international guidelines, which consider PAIR and other percutaneous techniques contraindicated in AE due to the risk of biliary fistula and dissemination [14]. In contrast, 15.0% of CE cases were managed by non-resectional approaches, reflecting the appropriateness of PAIR for selected CE stages, particularly CE1 and CE3a according to WHO-IWGE classification [14]. The higher frequency of the ‘other’ procedure category outside Astana (19.5% vs. 3.0%, p = 0.008) is consistent with the pattern of case complexity described above (Study Setting, Methods): complex hepatobiliary resections for echinococcosis are performed deliberately at the three major tertiary centres (Astana, Almaty, and Karaganda), whereas elsewhere surgical intervention is typically limited to incidental findings or non-resectional management (ICD-9-CM 50.29), which includes both open cyst-evacuation techniques (enucleation, pericystectomy) and percutaneous drainage. Percutaneous drainage was more commonly practised earlier in the study period and has since been largely superseded by definitive surgical management under updated clinical protocols, a shift that may partly explain temporal and regional variation within this category.

The exclusive reliance on resectional and lobar procedures for AE observed in both the national and institutional cohorts is consistent with the wider international experience of centres managing high AE caseloads. Radical hepatic resection with a tumour-free margin remains the only potentially curative option for AE, yet even in expert hands only a minority of patients are eligible for radical resection at the time of diagnosis, as the disease is frequently detected only after invasion of major intrahepatic vascular or biliary structures [15]. Northwest China, which is estimated to account for the large majority of the global AE caseload, has developed the most extensive experience in managing such advanced, otherwise unresectable disease, including ex vivo liver resection with autotransplantation (ELRA) as an alternative to allogeneic liver transplantation for end-stage cases with extensive vascular involvement [16,17]. It should be noted that liver transplantation for AE, while outside the scope of the present resection-focused analysis, is performed in Kazakhstan exclusively at our institution: three patients underwent living-donor liver transplantation for advanced hepatic AE during the broader study window (2021, 2023, and 2025), including two cases requiring inferior vena cava replacement, representing the entire national experience with this treatment modality to date. As a distinct, highly specialised treatment pathway (ICD-9-CM 50.5x) reserved for the most advanced, otherwise unresectable stage of disease, transplantation was not captured by the resectional/destructive procedure codes used for case identification here. These cases are reported in detail in a dedicated technical case series [18], which complements the present study by describing the management of end-stage AE beyond the resection-based surgical burden characterised in this analysis.

Several further methodological points warrant clarification. First, seropositivity in the NROC cohort (Table 4) reflects diagnostic testing among patients already selected for surgical intervention on other clinical and imaging grounds, rather than population-level screening or a criterion for surgical indication; the World Health Organisation does not recommend serology as a screening tool for community-based echinococcosis surveys, given its inability to reliably distinguish active from inactive or past infection. Second, this study was restricted by design to hepatic localisation; extrahepatic disease, including pulmonary echinococcosis, which represents a clinically important site of involvement, particularly for CE, was not captured and may represent a substantial additional burden not reflected in the present figures. Third, although postoperative length of hospital stay was recorded and compared (Table 4), the longer stay observed in AE patients (median 12 vs. 10 days, p = 0.015) is consistent with the more extensive hepatic resections typically required for the infiltrative growth pattern of AE; comparable differences in recovery time according to resection extent have been reported elsewhere, with open resection for AE associated with substantially longer hospital stays than less extensive or laparoscopic approaches [19]. Fourth, data on postoperative complications and mortality were not analysed in this study, as this fell outside its defined scope; these outcomes are recorded in a separate institutional database and are planned for a dedicated future study on complications and recurrence once a sufficient patient cohort has accumulated.

Several limitations of this study should be acknowledged. First, the data are aggregated administrative records without patient-level clinical detail; cyst size, WHO-IWGE stage, operative findings, perioperative complications, and long-term outcomes are unavailable. Second, 6.3% of cases were coded as unspecified hepatic echinococcosis (B67.8), introducing diagnostic uncertainty. Third, the three-year observation window is insufficient for formal trend analysis, and Mann–Kendall or regression-based methods were not applicable. Fourth, regional variation in coding practice and referral patterns may contribute to apparent geographic differences. Fifth, the national dataset does not include a distinct procedure code for reoperations; a patient undergoing repeat surgery for recurrence could therefore not be reliably distinguished from a new case, potentially inflating national case counts to an unknown degree (this limitation does not apply to the NROC series, where repeat procedures were identifiable from clinical records). Despite these limitations, national administrative data provide a population-level perspective not achievable from single-institution series and establish a baseline for longitudinal monitoring.

Future research should prioritise the development of a national clinical registry for echinococcosis linking operative data with patient demographics, imaging classification, intraoperative findings, and long-term outcomes, following models such as the French National Reference Centre registry for AE, which has tracked epidemiological and clinical trends since 1982 [13]. Integration with veterinary and environmental surveillance data within a One Health framework would further strengthen the evidence base for national control and prevention strategies.

5. Conclusions

This nationwide administrative data analysis demonstrates that the surgical management of hepatic echinococcosis in Kazakhstan is undergoing measurable change: a rising, though not yet statistically significant, share of cases are attributable to the more aggressive alveolar form, and surgical care—particularly for AE—is increasingly concentrated in a small number of tertiary hepatobiliary centres, principally Astana and Almaty. Cystic and alveolar echinococcosis differ systematically in their surgical management, with AE managed exclusively by resectional or lobar procedures, consistent with international treatment guidelines, and associated with longer postoperative hospital stays than CE. Liver transplantation for advanced AE, while outside the scope of the present resection-focused analysis, is already being performed in Kazakhstan, underscoring that the country’s surgical capacity for this disease spans the full spectrum from routine resection to complex transplant surgery. Taken together, these findings support three concrete priorities for national health system planning: the development of a national echinococcosis registry to enable systematic, longitudinal surveillance of both surgical volume and outcomes; the formalisation of referral pathways for complex hepatobiliary parasitic disease, particularly AE, to complement the informal centralisation already observed; and continued investment in specialised surgical and transplant capacity to meet the needs of patients with advanced disease. Future work should extend this administrative-data approach to include postoperative complications, mortality, and recurrence, and should seek to integrate clinical, veterinary, and environmental surveillance data within a One Health framework.