The effects of exercise and mitochondrial transplantation alone or in combination against Doxorubicin-induced skeletal muscle atrophy.

Doxorubicin (DOX) is a chemotherapy drug used to treat various types of cancer, but it is associated with significant side effects such as skeletal muscle atrophy. Exercise has been found to prevent skeletal muscle atrophy through the modulation of mitochondrial pathways. Mitochondrial transplantation (MT) may mitigate toxicity, neurological disorders, kidney and liver injury, and skeletal muscle atrophy. The objective of this study was to evaluate the effects of MT, exercise, and MT with exercise on DOX-induced skeletal muscle atrophy. Male Sprague Dawley rats were randomly assigned to the following groups: control, DOX, MT with DOX, exercise with DOX, and exercise with MT and DOX. A 10-day treadmill running exercise and MT (6.5 µg/100 µL) to tibialis anterior (TA) muscle were administered prior to a single injection of DOX (20 mg/kg). Our data showed that exercise and MT with exercise led to an increase in cross-sectional area of the TA muscle. Exercise, MT and MT with exercise reduced inflammation and maintained mitochondrial enzyme activity. Additionally, exercise and MT have been shown to regulate mitochondrial fusion/fission. Our findings revealed that exercise and MT with exercise prevented oxidative damage. Furthermore, MT and MT with exercise decreased apoptosis and MT with exercise triggered mitochondrial biogenesis. These findings demonstrate the importance of exercise in the prevention of skeletal muscle atrophy and emphasize the significant benefits of MT with exercise. To the best of our knowledge, this is the first study to demonstrate the therapeutic effects of MT with exercise in DOX-induced skeletal muscle atrophy.

Time-course and muscle-specific gene expression of matrix metalloproteinases and inflammatory cytokines in response to acute treadmill exercise in rats.

BACKGROUND: The extracellular matrix (ECM) of skeletal muscle plays a pivotal role in tissue repair and growth, and its remodeling tightly regulated by matrix metalloproteinases (MMPs), tissue inhibitors of metalloproteinases (TIMPs), and inflammatory cytokines. This study aimed to investigate changes in the mRNA expression of MMPs (Mmp-2 and Mmp-14), TIMPs (Timp-1 and Timp-2), and inflammatory cytokines (Il-1ß, Tnf-α, and Tgfß1) in the soleus (SOL) and extensor digitorum longus (EDL) muscles of rats following acute treadmill exercise. Additionally, muscle morphology was examined using hematoxylin and eosin (H&E) staining. METHODS AND RESULTS: Male rats were subjected to acute treadmill exercise at 25 m/min for 60 min with a %0 slope. The mRNA expression of ECM components and muscle morphology in the SOL and EDL were assessed in both sedentary and exercise groups at various time points (immediately (0) and 1, 3, 6, 12, and 24 h post-exercise). Our results revealed a muscle-specific response, with early upregulation of the mRNA expression of Mmp-2, Mmp-14, Timp-1, Timp-2, Il-1ß, and Tnf-α observed in the SOL compared to the EDL. A decrease in Tgfß1 mRNA expression was evident in the SOL at all post-exercise time points. Conversely, Tgfß1 mRNA expression increased at 0 and 3 h post-exercise in the EDL. Histological analysis also revealed earlier cell infiltration in the SOL than in the EDL following acute exercise. CONCLUSIONS: Our results highlight how acute exercise modulates ECM components and muscle structure differently in the SOL and EDL muscles, leading to distinct muscle-specific responses.

Neurocognitive responses to spatial design behaviors and tools among interior architecture students: a pilot study.

The impact of emotions on human behavior is substantial, and the ability to recognize people's feelings has a wide range of practical applications including education. Here, the methods and tools of education are being calibrated according to the data gained over electroencephalogram (EEG) signals. The issue of which design tools would be ideal in the future of interior architecture education, is an uncertain field. It is important to measure the students' emotional states while using manual and digital design tools to determine the different impacts. Brain-computer interfaces have made it possible to monitor emotional states in a way that is both convenient and economical. In the research of emotion recognition, EEG signals have been employed, and the resulting literature explains basic emotions as well as complicated scenarios that are created from the combination of numerous basic emotions. The objective of this study is to investigate the emotional states and degrees of attachment experienced by interior architecture students while engaging in their design processes. This includes examining the use of 2D or 3D tools, whether manual or digital, and identifying any changes in design tool usage and behaviors that may be influenced by different teaching techniques. Accordingly, the hierarchical clustering which is a technique used in data analysis to group objects into a hierarchical structure of clusters based on their similarities has been conducted.

Promising Outcome of Radiation Therapy for Chondroblastoma of Temporal Bone in Childhood: A Case Report.

Chondroblastoma is a rare cartilaginous benign bone tumor. Chondroblastoma in the temporal bone is also quite rare. Total excision is the main treatment. Data regarding tumor response to radiation therapy (RT) is insufficient. We describe a case of chondroblastoma that was treated with RT following subtotal tumor resection. In this case, the patient was a 14-year-old male who presented with a three-month history of ear fullness and hearing loss in his right ear. Magnetic resonance imaging revealed a mass partly filling the right external auditory canal and the inferior part of the middle ear. Histopathological findings indicated chondroblastoma. Subtotal tumor resection was performed due to risk of complications. RT was planned upon the growth of the tumor during follow-up. Treatment with subtotal resection and postoperative RT has been successful and the patient had no recurrence in the course of the 12-year follow-up. In chondroblastoma, complete surgical resection is still the gold standard. But the success of subtotal resection followed by adjuvant RT should also be kept in mind for cases where the total excision would pose high morbidity.

The Critical Role of Therapeutic Plasma Exchange in the Treatment of MPO-ANCA Associated Crescentic IgA Nephropathy.

Crescentic IgA nephropathy (IgAN) with the positivity for antineutrophilic cytoplasmic antibody (ANCA) is a novel and uncommon entity. The optimal management of this condition is not well-defined. We report a 49-years-old woman with complaints of skin rash and swelling of lower limbs. She had hematuria, proteinuria and, progressive renal impairment with positive myeloperoxidase (MPO)-ANCA test. A renal biopsy revealed MPO-ANCA-associated crescentic IgAN. Induction therapy was intravenous methylprednisolone, cyclophosphamide and, therapeutic plasma exchange (TPE). An unexpected disease flare-up was observed during induction immunosuppressive therapy which regressed after long-term TPE. The patient experienced a full renal recovery after treatment with long-term TPE, cyclophosphamide, and corticosteroids.  DOI: 10.52547/ijkd.6490.

A knowledge-based self-pre-diagnosis system to predict Covid-19 in smartphone users using personal data and observed symptoms.

Covid-19 is an acute respiratory infection and presents various clinical features ranging from no symptoms to severe pneumonia and death. Medical expert systems, especially in diagnosis and monitoring stages, can give positive consequences in the struggle against Covid-19. In this study, a rule-based expert system is designed as a predictive tool in self-pre-diagnosis of Covid-19. The potential users are smartphone users, healthcare experts and government health authorities. The system does not only share the data gathered from the users with experts, but also analyzes the symptom data as a diagnostic assistant to predict possible Covid-19 risk. To do this, a user needs to fill out a patient examination card that conducts an online Covid-19 diagnostic test, to receive an unconfirmed online test prediction result and a set of precautionary and supportive action suggestions. The system was tested for 169 positive cases. The results produced by the system were compared with the real PCR test results for the same cases. For patients with certain symptomatic findings, there was no significant difference found between the results of the system and the confirmed test results with PCR test. Furthermore, a set of suitable suggestions produced by the system were compared with the written suggestions of a collaborated health expert. The suggestions deduced and the written suggestions of the health expert were similar and the system suggestions in line with suggestions of the expert. The system can be suitable for diagnosing and monitoring of positive cases in the areas other than clinics and hospitals during the Covid-19 pandemic. The results of the case studies are promising, and it demonstrates the applicability, effectiveness, and efficiency of the proposed approach in all communities.

A rule-based decision support system for aiding iron deficiency management.

Iron is a vital mineral for the proper function of hemoglobin which is also a protein needed to transport oxygen in the blood. The lack of iron in human blood causes a range of serious health problems including "anemia." In this article, the COntAneRS (Clinical ONTology-based Iron Deficiency-ANEmia- Recommendation System) is proposed as a clinical decision support system to diagnose iron deficiency and manage its treatment. The applied methodologies and main technical contributions of this study are discussed in four aspects: (1) Iron Deficiency Domain Ontology (IDDOnt), (2) Semantic Web Rule Knowledgebase (SWRL), (3) Inference Engine, and (4) Physician Portal of the system. Experimental studies of the proposed system have been applied on a population of 200 people, consisting of real anemia patients and healthy individuals. First, a decision tree classifier is used to diagnose iron deficiency condition based on the patients' demographic information and certain medical data, as well as recently measured hemoglobin CBC levels of the patients. To check the effectiveness of the system, the data of 50 anonymous patients randomly selected from 200 patients are entered manually in the IDDOnt and the system is then verified according to the inferencing results. After inferencing step, the recommendations related to appropriate iron drugs, daily consumption dose, drug consumption periods, and additional medical suggestions about drug interactions are provided by the system to the responsible physician through system ontology, SWRL rules, and web services. As a result of experimental studies, our system has provided very good accuracy (99.5%) and robust results in producing patient-suitable suggestions. In addition, the applicability of the system on the cases is discussed as case studies in this paper. The results reported from the applied case studies are promising in demonstrating the applicability, effectiveness, and efficiency of the proposed approach.

Investigation of the effect of isolated mitochondria transplantation on renal ischemia-reperfusion injury in rats.

Ischemia/Reperfusion (I/R) injury is clinically important in many surgical practice including kidney transplantation. It is known that mitochondria have a key role in the intracellular and extracellular signaling pathways of ischemia and reperfusion injury. In this respect, we pointed to explore the probable effects of isolated mitochondria transplantation from MSCs (mesenchymal stem cells), to alleviate ischemia/reperfusion-induced renal injury. Experiments were held on the 48 male Sprague Dawley rats. Groups were divided as Control (C1), I/R-Control (C2), Vehicle-1 (V1), Vehicle-2 (V2), Transplantation-1 (T1) and Transplantation-2 (T2) group. Unilaterally nephrectomy was performed in all groups. In the groups except the control, the left kidneys ischemized for 45 min and then reperfusion was carried out. According to the study groups, isolated mitochondria or vehicle infused into the renal cortex and rats were monitored for 48 h. Following that mentioned procedure, animals were sacrificed and biological samples were taken for physiological, histological and biochemical examinations. The results of present study show that mitochondrial transplantation promoted proliferation and regeneration of tubular cells after renal injury. Moreover, mitochondrial transplantation reduced mitochondrial dynamics-DRP-1 fission protein of tubular cells and reversed renal deficits. Mitochondrial transplantation diminished apoptotic markers including TUNEL and Caspase-3 levels in injured renal cells. Our results provide a direct link between mitochondria dysfunction and ischemia/reperfusion-induced renal injury and suggest a therapeutic effect of transplanting isolated mitochondria obtained from MSCs against renal injury.

The effects of mitochondrial transplantation in acetaminophen-induced liver toxicity in rats.

AIMS: Acetaminophen (APAP) toxicity is one of the leading causes of acute liver injury-related death and liver failure worldwide. In many studies, mitochondrial dysfunction has been identified as an important cause of damage in APAP toxicity. Therefore, our study aimed to investigate the possible effects of mitochondrial transplantation on liver damage due to APAP toxicity. MAIN METHODS: APAP toxicity model was implemented by administering a toxic dose of APAP. To demonstrate the efficiency of mitochondria transplantation, it was compared with N-acetylcysteine (NAC) application, which is now clinically accepted. Mitochondrial transplantation was carried out by delivering mitochondria to the liver via the portal circulation, which was injected into the spleen. In our study, the rats were randomly divided into 6 groups as Sham, APAP, Control 1, APAP+mito, Control 2, and APAP+NAC. In the end of the experiment, histological and biochemical analysis were performed and the biodistribution of the transplanted mitochondria to target cells were also shown. KEY FINDINGS: Successful mitochondrial transplantation was confirmed and mitochondrial transplantation improved the liver histological structure to a similar level with healthy rats. Moreover, plasma ALT levels, apoptotic cells, and total oxidant levels were decreased. It was also observed that NAC treatment increased GSH levels to the highest level among the groups. However, mitochondrial transplantation was more effective than NAC application in terms of histological and functional improvement. SIGNIFICANCE: It has been evaluated that mitochondrial transplantation can be used as an important alternative or adjunctive treatment method in liver damage caused by toxic dose APAP intake.

The effects of mesenchymal stem cell mitochondrial transplantation on doxorubicin-mediated nephrotoxicity in rats.

The effect of dysfunctional mitochondria in several cell pathologies has been reported in renal diseases, including diabetic nephropathy and acute kidney injury. Previous studies have reported that mitochondrial transplantation provided surprising results in myocardial and liver ischemia, as well as in Parkinson's disease. We aimed to investigate the beneficial effects of isolated mitochondria transplantation from mesenchymal stem cells (MSCs) in vivo, to mitigate renal damage that arises from doxorubicin-mediated nephrotoxicity and its action mechanism. In this study, a kidney model of doxorubicin-mediated nephrotoxicity was used and isolated mitochondria from MSCs were transferred to the renal cortex of rats. The findings showed that the rate of isolated mitochondria from MSCs maintains sufficient membrane integrity, and was associated with a beneficial renal therapeutic effect. Following doxorubicin-mediated renal injury, isolated mitochondria or vehicle infused into the renal cortex and rats were monitored for five days. This study found that mitochondrial transplantation decreased cellular oxidative stress and promoted regeneration of tubular cells after renal injury (P < .001, P = .009). Moreover, mitochondrial transplantation reduced protein accumulation of tubular cells and reversed renal deficits (P = .01, P < .001). Mitochondrial transplantation increased Bcl-2 levels, and caspase-3 levels decreased in injured renal cells (P < .015, P < .001). Our results provide a direct link between mitochondria dysfunction and doxorubicin-mediated nephrotoxicity and suggest a therapeutic effect of transferring isolated mitochondria obtained from MSCs against renal injury. To our knowledge, this study is the first study in the literature that showed good therapeutic effects of mitochondrial transplantation in a nephrotoxicity model, which is under-researched.

A decision support system on the obesity management and consultation during childhood and adolescence using ontology and semantic rules.

BACKGROUND: Obesity is defined as abnormal or excessive fat accumulation that presents a risk to health according to the World Health Organization (WHO). Pediatric or childhood obesity is the most prevalent nutritional disorder among children and adolescents worldwide. In pediatric or childhood obesity, constant monitoring of the pediatric patients by health experts is required to provide efficient obesity management and treatment. Therefore, the patients are examined on a regular basis, the measurements are compared against predefined percentile values and the development of the pediatric patient is examined. RESULTS: This study discusses the design, implementation, and potential use of an ontology-based obesity management and consultation system which is a decision support system for health experts during treatments of the children and adolescent patients. The system does not only share instant gathered medical data to health experts but also examines the data as a smart medical assistant. The system includes an ontology-based inference engine module, which is a decision support module, and used to infer certain personalized suggestions for patients. Suggestions in four categories emerged as a result: (1) Development Feedback Suggestions, (2) Calorie Intake Suggestions and Physical Activities, (3) Mom Suggestions, and (4) Obesity Treatment Stage Suggestions. The methodologies applied and main technical contributions are discussed in three aspects: (1) Obesity Tracking Ontology, (2) Semantic Web Rule Knowledge base, and (3) Inference Engine Module. In this study, unlike other similar studies, ontology and rule based smart medical assistant which have different functionalities from adults' obesity management is considered especially for obesity management of children and adolescents. The system also includes intensive pediatric health care expert involvement. Eighty case studies from real anonymous pediatric patients are analyzed and discussed in this experimental study. CONCLUSIONS: The results retrieved from 80 case studies are promising in demonstrating the applicability, effectiveness and efficiency of the proposed approach. The inference engine module of the proposed system can be integrated semantically into intelligent and distributed decision support systems, and the system ontology can be used as a knowledge base in similar systems.

Prominent Signet Ring Cell Morphology in a Pulmonary Squamous Cell Carcinoma.

In daily practice, signet ring cell morphology immediately brings to the mind the possibility of an adenocarcinoma at first glance. The signet ring cell appearance has been described and is well-known in a wide variety of some other neoplasms as well. Surprisingly however, neoplastic cells having the same morphology can unexpectedly be encountered in not previously well-documented tumors. Here, we present an 85-year-old man diagnosed with primary pulmonary squamous cell carcinoma and a large signet ring cell population. Examination of the lobectomy specimen and further radiological workup was consistent with stage I disease. Signet ring cell variant of squamous cell carcinoma is a very infrequent tumor and has been reported in only eight cases from skin, cervical and oral cavity biopsies as well as in one case of pulmonary acantholytic variant of squamous cell carcinoma with focal signet ring cells. To be aware of this entity is crucial for pathologists to reach the correct diagnosis, particularly in cytological samples, because of its potentially modifying effect on treatment options and patient management compared to adenocarcinomas. Our patient remained in clinical remission during the 9-month follow-up.

FoodWiki: a Mobile App Examines Side Effects of Food Additives Via Semantic Web.

In this article, a research project on mobile safe food consumption system (FoodWiki) is discussed that performs its own inferencing rules in its own knowledge base. Currently, the developed rules examines the side effects that are causing some health risks: heart disease, diabetes, allergy, and asthma as initial. There are thousands compounds added to the processed food by food producers with numerous effects on the food: to add color, stabilize, texturize, preserve, sweeten, thicken, add flavor, soften, emulsify, and so forth. Those commonly used ingredients or compounds in manufactured foods may have many side effects that cause several health risks such as heart disease, hypertension, cholesterol, asthma, diabetes, allergies, alzheimer etc. according to World Health Organization. Safety in food consumption, especially by patients in these risk groups, has become crucial, given that such health problems are ranked in the top ten health risks around the world. It is needed personal e-health knowledge base systems to help patients take control of their safe food consumption. The systems with advanced semantic knowledge base can provide recommendations of appropriate foods before consumption by individuals. The proposed FoodWiki system is using a concept based search mechanism that performs on thousands food compounds to provide more relevant information.

Distinctive immunostaining of claudin-4 in spiradenomas.

The intercellular bridges are essential structures in maintaining the histologic organization of the epithelium, while providing a very efficient way to exchange molecules between cells and transduction of the cell-to-cell and matrix-to-cell signals. Derangement in those important structures' physical integrity and/or function, which can be assessed by the presence or absence of several intercellular bridge proteins including claudin-4, E-cadherin, and ß-catenin, was found to be related to several phenomena in the path to the neoplastic transformation. However, these proteins have not been studied in the wide variety of the skin neoplasms, in detail. Herein, we immunohistochemically assessed the expression patterns of these 3 intercellular bridge proteins on a total of 86 epidermal and eccrine adnexal tumors including basal cell carcinoma, squamous cell carcinoma, poroma, spiradenoma, syringoma, and hidradenoma. We observed a selective and distinct claudin-4 expression in the ductal-type cells of all cases of spiradenomas. Similarly, in the poromas, syringomas, and hidradenomas, claudin-4 was only positive in the luminal cells of microcystic structures, although not as conspicuous as in the spiradenomas. On the other hand, E-cadherin and ß-catenin were positive in almost all types of the tumors, in a way which was not contributory to differentiate from each other. In conclusion, we think that claudin-4 can be helpful at least in making a reliable differential diagnosis of spiradenoma when overlapping morphologic features do not allow to further subclassification in the overwhelming variety of the adnexal tumors.

TraG encoded by the pIP501 type IV secretion system is a two-domain peptidoglycan-degrading enzyme essential for conjugative transfer.

pIP501 is a conjugative broad-host-range plasmid frequently present in nosocomial Enterococcus faecalis and Enterococcus faecium isolates. We focus here on the functional analysis of the type IV secretion gene traG, which was found to be essential for pIP501 conjugative transfer between Gram-positive bacteria. The TraG protein, which localizes to the cell envelope of E. faecalis harboring pIP501, was expressed and purified without its N-terminal transmembrane helix (TraGΔTMH) and shown to possess peptidoglycan-degrading activity. TraGΔTMH was inhibited by specific lytic transglycosylase inhibitors hexa-N-acetylchitohexaose and bulgecin A. Analysis of the TraG sequence suggested the presence of two domains which both could contribute to the observed cell wall-degrading activity: an N-terminal soluble lytic transglycosylase domain (SLT) and a C-terminal cysteine-, histidine-dependent amidohydrolases/peptidases (CHAP) domain. The protein domains were expressed separately, and both degraded peptidoglycan. A change of the conserved glutamate residue in the putative catalytic center of the SLT domain (E87) to glycine resulted in almost complete inactivity, which is consistent with this part of TraG being a predicted lytic transglycosylase. Based on our findings, we propose that TraG locally opens the peptidoglycan to facilitate insertion of the Gram-positive bacterial type IV secretion machinery into the cell envelope.

CD138 expression in renal tumors and its usage in the differential diagnosis.

OBJECTIVE: The differential diagnosis of kidney tumors, especially those with eosinophilic cytoplasms, can be problematic due to overlapping morphologic features. CD138 is primarily a plasma cell marker but is known to be expressed in the proximal renal tubular epithelium as well. This study aims to investigate the possible contribution of CD138 expression in the differential diagnosis of kidney tumors with eosinophilic cytoplasm. MATERIAL AND METHOD: The case series consisted of 15 chromophobe (ChRCC), 5 eosinophilic variant (EoRCC), 10 clear cell (CCRCC) and 9 papillary (PRCC) renal cell carcinomas, and 13 oncocytomas. Sections obtained from representative paraffin blocks were stained against CD138 antibody. RESULTS: All CCRCC and PRCC showed membranous CD138 expression. In some of the other eosinophilic renal tumors, cytoplasmic CD138 labeling in varying degrees was detected. In CCRCC cases, CD138 expression was especially observed in low grade areas and areas showing cystic and pseudopapillary growth patterns. A similar pattern of cytoplasmic staining was seen in 3 of the EoRCC and the most of the PRCC cases (6/9). CONCLUSION: Our findings suggest that CD138 may contribute to the differential diagnosis of renal tumors because of the membranous staining pattern in CCRCC and EoRCC cases and the cytoplasmic staining in CHRCC and oncocytoma cases. Its contributory role may be improved by combined usage with markers like Cytokeratin 7 and RCC marker.

Pure peroneal intraneural ganglion cyst ascending along the sciatic nerve.

Peroneal nerve entrapment is most commonly seen in the popliteal fossa. It is rarely caused by a ganglion. Intraneural ganglia, although uncommon and seldom cause serious complications, are well recognized and most commonly affect the common peroneal (lateral popliteal) nerve. Ganglionic cysts developing in the sheath of a peripheral nerve or joint capsule may cause compression neuropathy. The differential diagnosis should involve L5 root lesions, posttraumatic intraneural hemorrhage, nerve compression near the tendinous arch located at the fibular insertion of the peroneal longus muscle and nerve-sheath tumors. We present a unique case of a pure intraneural ganglion of the common peroneal nerve ascending along the sciatic nerve. This case underscores the importance of consideration of an intraneural ganglion cyst with sciatic nerve involvement.

Nuclear planimetry on the samples from cytologically overlapping proliferative breast lesions.

Differentiation of low-grade breast carcinomas from fibroadenomas with atypia on fine-needle aspiration cytology material may sometimes be problematic. In some cytological samples of these lesions, both the nuclei of cells and patterns of cell clusters display substantial overlapping morphological characteristics. Nuclear morphometry on cytological material is suggested as an ancillary method for the differential diagnosis in many lesions, including breast tumors. Twenty-five cytological samples obtained from patients with breast lesions, which were histopathologically confirmed as grade I ductal carcinomas (n=10), tubular carcinomas (n=5), and fibroadenomas with atypia (n=10), were utilized in this study. Eight geometric features of about 2002 nuclei from these tumors were measured. Discriminant analysis was performed on this data set in order to test the correct classification based on the eight measured variables. Statistical analyses were carried out with two fundamentally different approaches: in the first one, the entire data from all measured nuclei were used for classification. In the second one, a subset of data representing the 10% most deviated values of variables was extracted from the entire dataset to simulate the "selective examination" performed during classical morphologic evaluation. When the entire data was used in discriminant analysis, the overall performance in the correct classification rate was found to be approximately 50%, which was considered an unacceptable value in routine diagnostic practice. In the subset of data constructed with our systematic and reproducible "selection bias", the overall performance of correct classification rate of the same discriminant model improved substantially to 97%. Morphologic examination is actually based on selection. The use of data obtained from all of the cells in morphometry, as previously used in nearly all of the statistical methods, may cause a masking effect in diagnostically important features. Morphometric studies may seem to be useless when this effect is not taken into account. However, with a systematic and reproducible selection of the values with a proper "bias", morphometry may provide some discriminatory information in overlapping lesions.

Spinal hydatid cyst mimicking arachnoid cyst on magnetic resonance imaging.

BACKGROUND: Primary spinal hydatid cysts are uncommon and account for 1% of all cases of hydatid disease. Echinococcus granulosus is most often responsible for the cyst hydatid. Intradural, extramedullary involvement is rare. When the cysts do not demonstrate typical magnetic resonance imaging findings, the differential diagnosis is more complex. METHOD: Case report. FINDINGS: An isolated primary hydatid cyst of the spine in a 35-year-old man that appeared to be an arachnoid cyst on preoperative radiographic examination. CONCLUSION: Hydatid cysts that lack the typical radiographic appearance may be mistaken for arachnoid cysts. Misdiagnosis has serious implications for surgical intervention and long-term care.