Extra-hepatopulmonary cystic echinococcosis in Bulgaria: frequency, management and outcome of the disease.

In the endemic countries, human cystic echinococcosis (CE) poses a serious medical and social problem. Because it most often affects the liver and lungs we aimed to define the proportion of cases with different organ localization, the diagnostic and therapeutic approaches in such cases, and the outcome of them. For a period 2010-2019, a total of 2863 cases of CE were registered in Bulgaria, of which 148 (5.17%) with organ localization other than liver and/or lung. The majority of patients with extra-hepatopulmonary localization of CE were adults. The distribution by gender showed predominance of female patients (57.43%) over those of males and primary cases (85.14%) exceeded the cases of recurrence. According to our study most common is the spleen involvement, followed by involvement of the abdominal cavity, kidneys and muscle/subcutaneous tissue. Other extra-hepatopulmonary organ localizations are significantly less common. This study shows that the extra-hepatopulmonary localization of CE is not so rare, and in most cases it is a primary disease. In respect of this, clinicians should consider hydatidosis in the differential diagnosis when cystic formation(s) is found, regardless of the organ involved.

A multiplex PCR for differential detection of Echinococcus granulosus sensu stricto, Echinococcus multilocularis and Echinococcus canadensis in China.

BACKGROUND: Echinococcosis caused by Echinococcus is one of the most major infectious diseases in north-west highland of China. E. granulosus sensu strict, E. multilocularis, and E. canadensis are known to be the only three species related to human health transmitting in the areas. To achieve targeted treatment and control of echinococcosis, the accurate identification and discrimination of the species are important. However, currently the available diagnostic approaches do not present ideal results either in accuracy or efficiency. METHODS: In the study, a set of primers were designed to aim at the three human-pathogenic Echinococcus species in China. The one-step multiplex PCR assay was developed and evaluated for the specificity and sensitivity. A total of 73 parasitic lesions and 41 fecal materials obtained from human and various animals collected in the clinic and the field were tested to assess the applicability of this method. RESULTS: The multiplex PCR effectively detected the individual DNA from the targeted species and their random mixtures generating with distinguishable expected size of products. The detection limit of the assay for each of the three species was 5 pg/µl when they were tested separately. When DNA mixtures of the targeted species containing the same concentration were used as templates, the lowest amount of DNA which can be detected was 50 pg/µl, 10 pg/µl and 5 pg/µl for E. granulosus s. s., E. multilocularis, and E. canadensis respectively. No cross-reactivity was observed when DNA from eight genetically close species was used as control templates. The multiplex PCR identifications of all samples were in line with the original sequencing results except for those infected with E. shiquicus, which showed negative signals in the developed assay. Of all the tested stool materials, 16 were previously found positive for Echinococcus by visual and microscopic examination. Among these 16 samples, 13 were confirmed by the multiplex PCR, and the other three tested negative. Additionally, the multiplex PCR identified another 14 positive feces from the remained 25 stool samples which absence of worms. CONCLUSIONS: The developed multiplex PCR shows advantages in fast diagnosis and large-scale epidemiological investigation, which proven to be a promising tool utilized in clinic and surveillance system.

Validation of a one-step PCR assay for the molecular identification of Echinococcus granulosus sensu stricto G1-G3 genotype.

The Italian National Reference Center for Echinococcosis (CeNRE, Sassari, Italy) set up a diagnostic protocol of "one-step-PCR" useful for the detection of E. granulosus sensu stricto (E.g.s.s.) and the identification of its genotype (G1-G3). The purpose of this work was to perform the validation of the "PCR E.g.s.s." method. The procedures were performed employing the criteria of the World Organization for Animal Health as well as of the Italian Accreditation Body (ACCREDIA) based on the Regulation UNI CEI EN ISO/IEC 17025. Positive DNA samples belonging to E. granulosus, E. ortleppi, E. multilocularis, E. canadensis species were used for the experiments. Analytical specificity evidenced primer pairs Cal (Calreticulin l gene of 1001 bp) with an specificity higher respect to Ef1 (Elongation-Factor 1 Alpha gene of 706 bp) and NAD (Dehydrogenase-subunit 1 gene of 219 bp). The analytical sensitivity presented the capability to detect a very low amount of parasite DNA corresponding to a concentration of 12.5 pg/µl; accuracy and precision related to the operator performance, along with repeatability and reproducibility, evidenced high concordance among results and demonstrated an excellent κ values of Cohen. According to the good performance related to the evaluated parameters, the method "PCR E.g.s.s." was suitable for the validation procedure, and consequently, to be undergone to the accreditation process. In conclusion, the results demonstrated an elevated robustness and reliable features of the "PCR E.g.s.s." able to perform a rapid diagnosis of E. granulosus in only "one step", hence, it is likely to avoid the sequencing step.

Progress towards international adoption of the World Health Organization ultrasound classification of cystic echinococcosis.

Cystic echinococcosis (CE) is a global parasitic zoonosis for which ultrasound (US) is the gold standard modality for diagnosis. In 2003, the WHO published a standardized US classification of CE, on which WHO treatment guidelines are based. In 2014, global adoption of the classification was questioned by a publication which indicated that, between 2004 and 2014, only half of studies utilizing a classification used the WHO classification. More recent studies have demonstrated that the WHO classification best reflects the natural history of CE, and is used with high reliability by experts in the field; despite these attributes, the classification's impact is ultimately limited by the extent of its adoption. A PubMed search using the terms "Echinococcus granulosus ultrasound," "Echinococcus granulosus classification," "cystic echinococcosis ultrasound," and "cystic echinococcosus classification" revealed publications on human CE utilizing a US classification. Classification(s) used, year of publication, and the country of the first author's institution were recorded. From 2004 to 2010, the WHO classification was used in 50% or fewer of included publications for 6 of the 7 years. After 2011, it appeared in a low of 75% (2013) to a high of 96% (2017) of included publications. Of all included studies published from 2004 to 2017, the WHO classification was referenced in 18% (3 of 17) from Africa, 64% (32 of 50) from Asia, 79% (89 of 113) from Europe, 89% (8 of 9) from North America, and 100% (9 of 9) from South America. Findings suggest that the WHO classification has been progressively taking preference to other classifications, with rate of adoption depending on continent of origin of the research. Residual use of the classification developed by Dr. Hassen Gharbi of Tunisia in 1982, used widely prior to development of the WHO classification (which reversed two stages in Gharbi's classification in order to more closely reflect the natural history of CE) suggests that adoption of a new classification takes time and varies regionally.

First molecular characterization of Echinococcus granulosus (sensu stricto) genotype 1 among cattle in Sudan.

BACKGROUND: Echinococcus granulosus sensu lato (s.l.) is the causative agent of cystic echinococcosis (CE), which is a cosmopolitan zoonotic parasitic disease infecting humans and a wide range of mammalian species including cattle. Currently, little information is available on the genetic diversity of Echinococcus species among livestock in Sudan. In the present study, fifty (n = 50) hydatid cysts were collected from cattle carcasses (one cyst sample per animal) at Al-kadarou slaughterhouse, Khartoum North, Sudan. DNA was extracted from protoscolices and the germinal layer of each cyst and subsequently amplified by PCR targeting the mitochondrial NADH dehydrogenase subunit 1 (NADH-1) gene. The amplified PCR products were purified and subjected to direct sequencing for subsequent construction of phylogenetic tree and net work analysis. RESULTS: The phylogenetic tree revealed the presence of Echinococcus canadenesis genotype 6 (G6) in 44 cysts (88.0%), Echinococcus ortleppi genotype 5 (G5) in 4 cysts (8.0%) and Echinococcus granulosus sensu stricto (s.s) genotype 1 (G1) in 2 cysts (4.0%). The phylogenetic network analysis revealed genetic variation among the different haplotypes/genotypes. This report has provided, for the first time, an insight of the role of cattle in the transmission of the zoonotic G1 echinococosis. CONCLUSIONS: The results of the study illustrate that Sudanese breeds of cattle may play an important role in the transmission dynamics and the epidemiology of cystic echinococcosis in Sudan. This study reports the first molecular identification of E. granulosus s.s. in cattle in Central Sudan.

The natural history of cystic echinococcosis in untreated and albendazole-treated patients.

The World Health Organization (WHO) treatment protocols for cystic echinococcosis (CE) are based on the standardized ultrasound (US) classification. This study examined whether the classification reflected the natural history of CE in untreated and albendazole-treated patients. Data were collected during mass US screenings in CE endemic regions among transhumant populations, the Turkana and Berber peoples of Kenya and Morocco. Cysts were classified using the WHO classification. Patient records occurring prior to treatment, and after albendazole administration, were selected. 852 paired before/after observations of 360 cysts from 257 patients were analyzed. A McNemar-Bowker χ2 test for symmetry was significant (p<0.0001). 744 observations (87.3%) maintained the same class, and 101 (11.9%) progressed, consistent with the classification. Regression to CE3B occurred in seven of 116 CE4 cyst observations (6.0%). A McNemar-Bowker χ2 test of 1414 paired before/after observations of 288 cysts from 157 albendazole-treated patients was significant (p<0.0001). 1236 observations (87.4%) maintained the same class, and 149 (10.5%) progressed, consistent with the classification. Regression to CE3B occurred in 29 of 206 CE4 observations (14.1%). Significant asymmetry confirms the WHO classification's applicability to the natural history of CE and albendazole-induced changes. Regressions may reflect the stability of CE3B cysts.

Expert Reliability for the World Health Organization Standardized Ultrasound Classification of Cystic Echinococcosis.

Cystic echinococcosis (CE), a parasitic zoonosis, results in cyst formation in the viscera. Cyst morphology depends on developmental stage. In 2003, the World Health Organization (WHO) published a standardized ultrasound (US) classification for CE, for use among experts as a standard of comparison. This study examined the reliability of this classification. Eleven international CE and US experts completed an assessment of eight WHO classification images and 88 test images representing cyst stages. Inter- and intraobserver reliability and observer performance were assessed using Fleiss' and Cohen's kappa. Interobserver reliability was moderate for WHO images (κ = 0.600, P < 0.0001) and substantial for test images (κ = 0.644, P < 0.0001), with substantial to almost perfect interobserver reliability for stages with pathognomonic signs (CE1, CE2, and CE3) for WHO (0.618 < κ < 0.904) and test images (0.642 < κ < 0.768). Comparisons of expert performances against the majority classification for each image were significant for WHO (0.413 < κ < 1.000, P < 0.005) and test images (0.718 < κ < 0.905, P < 0.0001); and intraobserver reliability was significant for WHO (0.520 < κ < 1.000, P < 0.005) and test images (0.690 < κ < 0.896, P < 0.0001). Findings demonstrate moderate to substantial interobserver and substantial to almost perfect intraobserver reliability for the WHO classification, with substantial to almost perfect interobserver reliability for pathognomonic stages. This confirms experts' abilities to reliably identify WHO-defined pathognomonic signs of CE, demonstrating that the WHO classification provides a reproducible way of staging CE.

A study of morphological aspects of cystic echinococcosis in sheep in Sardinia.

We have investigated the morphological and structural aspects of hydatid cysts recovered from sheep raised in southern Sardinia during two surveys conducted over the 20 years since the last control attempt at the end of the 1980s. In the first study carried out during 1995-1997, a few years after the last control attempt, a total of 10,334 cysts were examined, recovered from 1029 infected sheep out of a total of 1375 inspected (prevalence 74.84%). In the second survey, conducted ten years later during the period 2005-2010 in the absence of specific control measures, a total of 6249 cysts were recovered from 916 parasitized sheep out of the 1414 examined (prevalence 64.78%). Cysts were grouped into 5 different types: "Unilocular", "Multisepted", "Calcified", "Caseous", "Hyperlaminated". Unilocular: fertile, consist of a single fluid-filled cavity; multisepted: generally sterile, fluid filled, with cavity divided into spheroidal chambers (3-dozen); calcified: sterile, small, with internal chambers almost virtual due to the thickening of internal septa; caseous: sterile, the cavity filled with a thick yellowish matrix; hyperlaminated: sterile, with a virtual cavity filled with extensively folded and overlapping sheets of hyperproduced laminated tissue. A thorough knowledge and the precise characterization of each type of lesion, making it possible to establish detailed parameters for cyst classification, appears very useful for the harmonization of data collection. From a surveillance and control perspective it is proposed that, in addition to other relevant epidemiological information, data from meat inspection be further improved, including morpho-functional indications about cyst type.

Genetic diversity of Echinococcus spp. in Russia.

In Russia, both alveolar and cystic echinococcoses are endemic. This study aimed to identify the aetiological agents of the diseases and to investigate the distribution of each Echinococcus species in Russia. A total of 75 Echinococcus specimens were collected from 14 host species from 2010 to 2012. Based on the mitochondrial DNA sequences, they were identified as Echinococcus granulosus sensu stricto (s.s.), E. canadensis and E. multilocularis. E. granulosus s.s. was confirmed in the European Russia and the Altai region. Three genotypes, G6, G8 and G10 of E. canadensis were detected in Yakutia. G6 was also found in the Altai region. Four genotypes of E. multilocularis were confirmed; the Asian genotype in the western Siberia and the European Russia, the Mongolian genotype in an island of Baikal Lake and the Altai Republic, the European genotype from a captive monkey in Moscow Zoo and the North American genotype in Yakutia. The present distributional record will become a basis of public health to control echinococcoses in Russia. The rich genetic diversity demonstrates the importance of Russia in investigating the evolutionary history of the genus Echinococcus.

[Retrospective study of the distribution and the fertility of hydatid cysts in the child in Tunisia]. / Étude rétrospective de la distribution et de la fertilité des kystes hydatiques chez l'enfant en Tunisie.

PURPOSE OF THE STUDY: Our aim was to study the distribution and the fertility of the hydatid cysts in function of the age and the sex of patients and to identify the strain(s) responsible(s) of the children hydatidosis. PATIENTS AND METHODS: We have analyzed a total of 241 cysts coming from 195 children aged 2 to 16 years operated in the CHU F. Bourguiba of Monastir during the period from November 1999 to December 2009. For each cyst, the localization and the fertility of the métacestode as well as age, sex and origin of the patient are listed. Identification of strains was carried out by PCR/RFLP and has targeted the ribosomal gene ITS1. RESULTS: The lung was the primary localization of cyst (61.8%) followed by the liver (34.85%). The greatest number of cases is observed in the age groups 4-9 years (138 cases) where children's infection is more frequent in the male than in the female sex. The fertility of the cyst was independent of its site or its size and no incidence of age of children was detected. The G1 sheep strain is responsible for the contamination of children. CONCLUSION: The cystic echinococcosis described as a young adult disease may actually observed at any age and remains a serious problem of public health in Tunisia.

Varied types of intracranial hydatid cysts: radiological features and management techniques.

BACKGROUND: Even when radiological images are considered pathognomic for intracranial hydatid cysts, subtle image characteristics are evident depending upon the status/types of hydatid cysts. These imaging features, if finely scrutinized, may help to modify conventional surgical techniques of cyst excision. METHODS: From January 2006 to December 2011, nine patients (male:female 7:2, age range 4-44 years, median 7 years) harbouring intracranial hydatid cysts were managed at our centre. In addition to CT scans, all patients underwent plain and contrast-enhanced MRI scans. Based on these radiological findings, the types of hydatid cysts were characterized into simple or complicated (infected) cysts. Complicated cysts were further differentiated into ruptured or intact subtypes based on imaging features. Surgical procedures including the Dowling water dissection technique, in addition to head rotation, were performed for removing these cysts intact. RESULTS: Children (n = 4) aged 6 years or less presented with increasing head size as the only complaint, while the rest of the patients (n = 5) had symptoms of raised intracranial pressure. MRI features of hypo-intensity on T1-weighted images, hyper-intensity on T2-weighted images, and non-contrast-enhancing cysts were noted for all simple cysts (n = 7), while iso- to mixed intensity on T1-weighted images and hyper-intensity on T2-weighted images with contrast-enhancing pericyst correctly diagnosed all complicated (infected) hydatid cysts (n = 2). One of these complicated cysts had spilled the infected contents outside the cyst wall, but within the confines of the cerebral parenchyma (pericyst). Such a case of contained spontaneously ruptured complicated hydatid cyst is described for the first time. At a median follow-up of 18 months, all patients remain free from cyst recurrence. CONCLUSION: Subtle changes in radiological features of CNS hydatid cysts should be appreciated so as to diagnose the type of cyst correctly. The surgical strategy should be tailored according to the type of cyst for favourable outcome.

Terminology and practice in control of some parasitic zoonoses.

Some terminology, based on tradition and still widely used in practice, is still scientifically incorrect.

Genetic classification of Echinococcus granulosus cysts from humans, cattle and camels in Libya using mutation scanning-based analysis of mitochondrial loci.

We genetically classified Echinococcus granulosus from humans, cattle and camels in Libya utilizing DNA regions (designated pcox1 and pnad1) within the cytochrome c oxidase subunit 1 (cox1) and NADH dehydrogenase 1 (nad1) mitochondrial genes, respectively. Polymerase chain reaction (PCR)-based single-strand conformation polymorphism (SSCP) analysis of pcox1 and pnad1 amplicons derived from genomic DNA samples from individual cysts (n = 176) revealed four distinct electrophoretic profiles for each locus. Direct sequencing of selected amplicons representing each of these profiles defined four different sequence types for each locus, which were present in five different combinations (designated haplotypes A-E) amongst all 176 isolates. Phylogenetic analysis of concatenated sequence data for these five haplotypes, together with a range of well-defined reference sequences, inferred that all cyst isolates from humans (n = 55) and a small number from cattle (13% of 38) belonged to the G1-G3 complex of E. granulosus (or E. granulosus sensu stricto), whereas most (87%) cysts from cattle and all 83 of them from camels were linked to the G6-G10 complex (or Echinococcus canadensis). The present study provides a foundation for future large-scale studies of the epidemiology and ecology of E. granulosus in Libya and other African countries.

Isolated omental hydatid cyst: clinical, radiologic, and pathologic findings.

Hydatid disease (HD) is a parasitic disease that is most commonly caused by the larval stage of Echinococcus granulosus. It is still a severe public health problem in the world and most commonly involves the liver and the lungs. However, HD can occur in almost any part of the body. Isolated omental hydatid cyst is one of the least common sites. Information about the appearance of cysts within the omentum is limited because of their extremely rare occurrence. In the evaluation of HD, clinical findings, serologic tests, and imaging methods such as plain radiography and ultrasonography are useful. This report describes the clinical, radiologic, and pathologic findings of omental hydatid cyst in addition to a literature review.

Magnetic resonance appearance of cerebral cystic echinococcosis: World Health Organization (WHO) classification.

BACKGROUND: Cystic echinococcosis (CE) of the brain is an uncommon parasitic infestation. The World Health Organization (WHO) recently published a classification of hepatic CE based upon ultrasonographic findings. PURPOSE: To evaluate whether the new WHO classification of hepatic CE can be used in the classification of cerebral CE. MATERIAL AND METHODS: The magnetic resonance (MR) imaging findings of 17 patients (14 male, three female), aged 10-24 years (mean age 16 years), with pathologically proved cerebral CE, and who underwent pre- and postcontrast MR imaging, were retrospectively evaluated. The cysts were classified according to the new WHO classification and their clinical stages. The MR imaging findings were correlated to the histopathologic findings. RESULTS: The fertile active cysts (n=12) that showed protoscoleces appeared as unilocular cysts with no visible wall (cystic lesions; CL), unilocular spherical cysts with a clear visible wall (CE1), or as a unilocular mother cyst with multiple vesicles arranged peripherally along the cyst wall (CE2). The transitional form (CE3) (n=2) containing scoleces showed multiple daughter cysts entirely filling the maternal cyst. The inactive cysts (n=3) that had lost their fertility appeared as a "ball of wool" with collapsed membrane or had detached membrane with water-lily sign (CE4) and calcified lesions (CE5). CONCLUSION: The WHO classification of hepatic CE can be used in the classification of cerebral CE when evaluated by MRI, as it can differentiate fertile active cysts from the transitional and inactive forms of cerebral cystic echinococcosis. This information is essential for treatment planning.

Species identification of human echinococcosis using histopathology and genotyping in northwestern China.

Human cystic echinococcosis, caused by infection with the larval stage of Echinococcus granulosus, and alveolar echinococcosis, caused by the larval form of E. multilocularis, are known to be important public health problems in western China. Echinococcus shiquicus is a new species of Echinococcus recently described in wildlife hosts from the eastern Tibetan plateau and its infectivity and/or pathogenicity in humans remain unknown. In the current study, parasite tissues from various organs were collected post-operatively from 68 echinococcosis patients from Sichuan and Qinghai provinces in eastern China. The tissues were examined by histopathology and genotyped using DNA sequencing and PCR-RFLP. Histopathologically, 38 human isolates were confirmed as E. granulosus and 30 as E. multilocularis. Mitochondrial cob gene sequencing and PCR-RFLP with rrnL as the target gene confirmed 33 of 53 of the isolates to have the G1 genotype of sheep/dog strain of E. granulosus as the only source of infection, while the remaining 20 isolates were identified as E. multilocularis. No infections were found to be caused by E. shiquicus. Additionally, 5 of 20 alveolar echinococcosis patients were confirmed to have intracranial metastases from primary hepatic alveolar echinococcosis lesions. All these cases originated from four provinces or autonomous regions but most were distributed in Sichuan and Qinghai provinces, where high prevalence rates of human alveolar echinococcosis and cystic echinococcosis were previously documented.

[Clinicoepidemiological features of echinococcosis in men serving in the navy].

AIM: To analyse echinococcosis morbidity and course characteristics in men serving in the Navy. MATERIAL AND METHODS: The results of annual 1983-2006 check-up of Navy men were analysed to estimate echinococcosis morbidity in patients with eosinophilia and tumors including cysts. The diagnosis was made with application of clinical, ultrasound, radionuclide, morphological (including parasitological), biochemical and immunological methods, computed tomography. RESULTS: 14 cases of hydatid echinococcosis were documented. Most of the patients (85.7%) were young (18-22 years of age). The patients were infected before the army in highly endemic regions. Solitary echinococcosis was detected in 8 patients. In multiple echinococcosis 1 patient had 4 cysts, 3 patients--3, 2 patients had 2 cysts. Echinococcosis of stage 1 was diagnosed in 3 patients, stage 2--in 11 patients. All the patients had cysts in the liver. In multiple echinococcosis the cysts occurred more often in the liver, spleen, kidney; they were rare in the lungs, bones, brain. Pain, asthenovegetative, dyspeptic and allergic syndromes were registered in 71.4, 28.6, 14.3 and 7.1 cases, respectively. Eosinophilia was encountered in 42.9% cases. These syndromes were, as a rule, weakly pronounced. Before accurate diagnosis 6 patients for 4-10 months were treated outpatiently for chronic gastroduodenitis, recurrent lumbalgia, biliary dyskinesia and intercostal neuralgia. CONCLUSION: Echinococcosis incidence rate in the Navy men is very low. They are infected before the army. The disease is diagnosed by chance or late, manifests primarily with pain symptoms.

Echocardiography findings in 16 cases of cardiac echinococcosis: proposal for a new classification system.

BACKGROUND: Echocardiography is a reliable method for diagnosing cardiac echinococcosis (CE). Currently, there is no echocardiographic classification system for CE, but such a scheme would facilitate diagnosis. This article presents echocardiographic data for 16 cases with CE and outlines a method for echocardiographic classification of CE based on the World Health Organization's ultrasonographic classification of cystic echinococcosis. METHODS: We assessed the echocardiographic features of hydatid cysts in 16 patients with CE (9 women and 7 men; mean age, 41 +/- 18.3 years), all of whom underwent cardiac surgery. The proposed classification system identifies 3 types of CE lesions: active (unilocular or multilocular and echolucent, showing double-layered cyst wall and hydatid sand); transitional (shrunken as a result of reduced intracystic pressure, and showing water lily sign); and inactive (completely degenerated contents creating the ball-of-wool sign). Preoperative echocardiographic findings (lesion location, imaging appearance [unilocular/multilocular, solid/semisolid], echocardiographic classification/type, number of lesions) were compared with computed tomographic, intraoperative echocardiographic, surgical, and parasitological findings. RESULTS: Preoperative echocardiography revealed 18 hydatid cysts (10 myocardial, 7 pericardial, 1 on the ascending aorta). In all, 10 lesions appeared multilocular, 6 unilocular, and 2 solid. A total of 11 were active, 5 transitional, and 2 inactive. Computed tomography identified 20 lesions total, therefore, two were missed on echocardiography. The preoperative echocardiographic findings correlated well with intraoperative echocardiographic, surgical, and parasitological findings. CONCLUSION: The 3 types of CE lesions defined in this proposed classification system feature distinct echocardiographic characteristics. This new system is reliable and practical, and could assist with diagnosis and rapid treatment of CE.

Ultrasound in tropical and parasitic diseases.

CONTEXT: Migration and worldwide travel mean that western clinicians and radiologists more and more face imported tropical diseases. Diseases with unclear signs and symptoms are likely to be investigated with ultrasound. Many tropical diseases have particular ultrasonographic features that are not familiar to the examiner and which may lead to further unnecessary or even harmful diagnostic investigations. In developing countries, ultrasound machines are becoming more widely distributed and are fairly cheap. Portable devices allow field use of ultrasound for population studies and individual diagnosis of tropical diseases. STARTING POINT: Recently, WHO introduced a standardised classification of ultrasonographic images of cystic echinococcosis (Acta Trop 2003; 85: 253-61), to obtain comparable results in patients worldwide and to link disease status with each morphological type of echinococcosis cyst. WHO also defined guidelines for the puncture, aspiration, injection of ethanol, and re-aspiration of such cysts. Ultrasound allows diagnosis of schistosomiasis-induced periportal fibrosis and bladder abnormalities. Liver abscesses can be differentiated from other focal lesions such as cysts or neoplasms. For amoebic abscesses, invasive procedures are usually not required. In doubtful cases ultrasound-guided puncture can give adequate material for microscopy and culture. Helminths (eg, ascaris), flukes, and filariae can be seen directly with ultrasound. Filaria-induced damage also includes hypoechogenic splenic foci and ultrasonographic abnormalities due to tropical hypereosinophilia. WHERE NEXT? Classification of cysts and procedures that are less invasive than conventional surgery are being developed further for cystic echinococcosis. Novel methods are needed for the assessment of polycystic and alveolar echinococcosis. Ultrasound protocols for schistosomiasis are being evaluated for interobserver reliability, relation to clinical disease status, and power to predict complications. A WHO expert-group is also developing a standardised protocol for Asian schistosomiasis. International consensus on an algorithm for managing amoebic liver abscesses is needed.

Unusual localizations of hydatid disease.

Hydatid disease is endemic in several Mediterranean countries, posing an important health problem for these countries. The hydatid cyst is characterized by cystic lesions with clear boundaries, which can be observed in all parts of the body. Approximately 70 % of hydatid cysts are situated in the liver, followed by the lung (25 %). The kidneys, spleen, bile ducts, mesentery, soft tissue and brain are less frequent sites. We investigated patients who were treated for hydatid disease in our departments in the last 5 years with respect to localization of the disease, symptoms, surgical intervention, length of hospitalization, diameters of the cyst, and classification by Gharbi. In this retrospective and descriptive study, 176 patients are evaluated who were treated for hydatid disease between 1995 and 1999 in our departments. Of these patients, 14 were included with localization other than in the liver and lungs. Fourteen of the patients diagnosed with unusually located hydatid disease were men, six were women. Their mean age was 41.6 +/- 20.8 years; the length of hospital stay was 7.07 +/- 0.4 days. Overall, 28.6 % of patients with unusually located hydatid cyst had recurrent disease. The time period since last cyst operation was 5.25 +/- 3.5 years. The mean cyst diameter was 96.5 +/- 54.5 mm. According to Gharbi's classification, three cases (21.4 %) of the unusually located hydatid cysts were type I, two (14.3 %) type II, and eight (57.1 %) type III. There was only one case of type IV and no cases of type V. Spleen and kidneys are the organs where hydatid disease is most frequently observed after the liver and lung. It can be observed in all parts of the body including the brain, peritoneum, mesenterium, choledochus, pancreas, bone and muscles. The type of treatment is determined by the localization and type of hydatid disease. Surgical treatment for splenic hydatid cysts is splenectomy. The functional kidney should be saved in non-communicable hydatid disease. Total excision is almost never possible; endocystectomy and drainage procedure should be preferred for hydatid disease of the brain, pancreas and choledochus. Chemotherapy is usually given because of the risk of recurrence; this medical treatment consists in albendazole and mebendazole administration for 3-6 months in the postoperative period.