[Gastrointestinal stromal tumor and renal transplant]. / Tumor del estroma gastrointestinal y trasplante renal.

Gastrointestinal stromal tumor (GIST) accounts for nearly 1% of all gastrointestinal tumors. Its association with renal transplantation is not frequent. Approximately 95% of GIST show staining for CD177. DOG1 is a recently described monoclonal antibody that shows positivity even in the absence of CD177 staining. The diagnosis of GIST should be pursued because of the availability of very effective treatments with tyrosine-kinase inhibitors. Herein, we describe the case of a woman with renal transplant who presented a small bowel GIST and weak positivity for CD177, treated initially with surgery. Tumor recurrence was documented 3 years later and histopatology showed loss of CD177 staining and positivity for DOG1. She was treated with imatimib without further recurrence after five years of follow up.

Clinicopathological features of aggressive B-cell lymphomas including B-cell lymphoma, unclassifiable, with features intermediate between diffuse large B-cell and Burkitt lymphomas: a study of 44 patients from Argentina.

Aggressive B-cell lymphomas incorporate a wide spectrum of lymphomas that pose challenges in diagnosis as well as treatment. We evaluated the clinicopathological features of 44 patients with aggressive B-cell lymphomas which were classified into 3 groups based on the World Health Organization 2008 classification as follows: including 30 cases of diffuse large B-cell lymphoma (DLBCL), 8 cases of Burkitt lymphoma (BL) and 6 cases of B-cell lymphoma, unclassifiable, with features intermediate between Burkitt lymphoma and diffuse large B-cell lymphoma (BCLU). Male predominance was observed in BL and BCLU groups and the mean age varied from 29 years in BL, 61 years in DLBCL and 70 years in BCLU. Patients with BCLU presented at more advanced stages and had a higher international prognostic index. By immunohistochemistry, they shared characteristics of both BL (including more frequent expression of SOX11) and DLBCL. FISH analyses showed three cases with more than one rearrangement: one MYC/BCL2 and two BCL2/BCL6, in addition to which one case with BCL2/IGH translocation and another with MYC rearrangement were also detected. The mean follow-up survival time of BCLU was 6.6 months, which was significantly shorter in comparison to DLBCL (31 months) and BL (30 months), respectively. The importance of recognizing this BCLU group relies on its different clinical course, poor prognosis and shorter survival than DLBCL and BL. An accurate diagnosis is critical for risk stratification and to improve therapeutic approaches and outcomes.

[Unusual presentation of plasma cell myeloma]. / Morfología dual de células de mieloma: inusual presentación de un caso.

A 41 year-old woman consulted because of facial pain. A magnetic resonance imaging showed a mass in the right petrous apex. A biopsy revealed a diffuse proliferation of large atypical cells with plasmablastic appearance, positive for CD138, BCL6, CD56 and p53. The proliferation factor was 80%. Monoclonal kappa light chain expression was observed. Because the unusual clinicopathological features the patient was studied to rule out systemic plasma cell myeloma. Bone scan disclosed multiple cranium osteolytic lesions; proteinogram showed hypogammaglobulinemia and immunofixation in serum and urine were negative. Afterwards, bone marrow biopsy was performed and it presented a 30% infiltration of the bone cylinder by mature plasma cells. These were monoclonal for kappa light chain with focal expression of p53 and without expression of CD56. These findings suggested the diagnosis of multiple myeloma. This case proposes a morphological spectrum of plasma cell neoplasms, showing a continuous clonal evolution of tumor cells, with an acquired plasticity of dedifferentiate, become immature and infiltrate extramedullary tissues, a fact possibly determined by accumulation of multiple genetic alterations. These findings confirm the difficulty of the differential diagnosis from histopathology study between plasmablastic lymphoma and plasmablastic transformation of plasma cell myeloma because of the nearly identical immunohistochemical profiles.

[Discrepancies between clinical diagnoses and autopsy findings]. / Discrepancias entre diagnósticos clínicos y hallazgos de autopsia.

The main objective of this study was to identify the clinical-pathological discrepancies in autopsies performed in the institution. We reviewed autopsies of clinical cases in 53 adults in the period between January 2005 and June 2009, carried out in the Pathology Service at the Hospital Privado de Córdoba, Argentina. Six autopsies were excluded due to insufficient information. The Goldman et al. classification was applied to establish clinico-pathologic discrepancies between clinical diagnoses and autopsy findings. Frequently clinical diagnoses were respiratory infections and acute pulmonary embolism. The most frequently reported postmortem diagnoses were respiratory infections and acute myocardial infarction. There were 17 major discrepancies and 30 coincidences. No any minor discrepancy was detected. Respiratory infections were the main cause of error, followed by myocardial infarction. We conclude that in 17/47 (37%) of cases the pre-mortem and postmortem diagnoses were different, and that respiratory infections were the main cause of error. We suggest to adopt educational and informative strategies, to revalue the importance of autopsy, and traditional clinical practices.

[Metastatic cardiac tamponade as initial manifestation of papillary thyroid carcinoma]. / Taponamiento cardíaco secundario a carcinoma papilar esclerosante difuso de tiroides.

Papillary carcinoma, diffuse sclerosing variant corresponds to 2% of all papillary thyroid carcinomas. It is usually diffuse and bilateral, affecting the entire gland. At the time of diagnosis, patients present lymph node and lung metastasis. It affects mainly young women. This case report describes a cardiac tamponade as the initial manifestation of an unusual variant of papillary thyroid carcinoma. A 32 year-old woman was attended at the emergency room with epigastric pain and dry cough. Physical examination revealed hypotension, tachycardia and decreased heart sounds. An echocardiogram confirmed severe pericardial effusion. Pericardial fluid cytology was positive for malignancy. The patient evolved with recurrent pericardial effusion and a pleuropericardial window was performed. At this procedure, a subpleural nodular lesion was found, which histology corresponded to metastases of papillary carcinoma, probably from thyroid origin. Total thyroidectomy was performed. The final diagnosis was papillary carcinoma, diffuse sclerosing variant. This variant infiltrates the connective tissue of the interfollicular spaces, mimicking thyroiditis and it is associated with early vascular permeation. This tumor, compared to the classic variants of thyroid carcinoma, is more aggressive and it has higher risk of recurrence. Papillary thyroid carcinoma should be considered as differential diagnosis in our population, in all metastatic papillary lesions, and even more in young female patients.

[Diffuse plane xanthomatosis associated with haematologic disorder and solid tumor. Findings of an autopsy]. / Xantomatosis plana difusa asociada a tumor hematológico y neoplasia sólida. Hallazgos de una autopsia.

Diffuse plane xanthomatosis associated with haematologic disorder and solid tumor. Findings of an autopsy. Diffuse plane xanthomatosis is an uncommon subtype of non-Langerhans histiocytosis. We report a case of a 78 year-old woman with a history of monoclonal gammopathy of undetermined significance and diffuse plane xanthomatosis since 1995. She consulted for malaise and died four days after admission. Autopsy was requested. Findings were diffuse plane xanthomatosis with extensive involvement of internal organs, lymphoplasmacytic lymphoma and cecal adenocarcinoma. Final event was acute bronchopneumonia. This entity is a subtype of histiocytosis. It affects skin and involves mucous membranes in 40% of the cases. Extracutaneous extension has been reported. It is usually associated with haematologic disorders. In this case, the patient had a lymphoplasmacytic lymphoma and colonic adenocarcinoma. We highlight the importance of recognition its association with monoclonal gammopathies and solid tumors in order to make a proper follow up of patients.

[26 year-old male patient with bone marrow transplantation. Report of a partial autopsy]. / Paciente de 26 años trasplantado de médula ósea. Reporte de autopsia parcial.

26 year-old male patient with diagnosis of acute lymphoblastic leukemia in 2006, who underwent chemotherapy and suffered a relapse and pulmonary aspergillosis as a complication. In 2009, he received bone marrow transplant. After it, he developed cutaneous and intestinal graft versus host disease (GVH). He was admitted for diarrhea. Then he presented grade IV dyspnea, patchy alveolar infiltrates on chest computed tomography and pancytopenia with impaired renal function as laboratory findings. He entered Intensive Care Unit, dying 7 days later. The oncologist who discussed the case defined this patient as a high risk case because of type of transplant received, relapse and complications. His diagnostic hypotheses were: CMV infection, pulmonary aspergillosis reactivation, chronic GVH, Pneumocystis jiroveci infection, mycobacteriosis and pseudomembranous colitis. Partial autopsy revealed diffuse intra-alveolar hemorrhage, diffuse alveolar damage, right pulmonary infarction with microthrombosis and bronchiolitis obliterans organizing pneumonia.

[Spontaneous mediastinal hematoma as initial presentation of cystic adenoma of ectopic parathyroid]. / Hematoma mediastinal espontáneo secundario a ruptura de adenoma quístico de paratiroides ectópica.

Spontaneous mediastinal hematoma as initial presentation of cystic adenoma of ectopic parathyroid Atraumatic spontaneous mediastinal hematomas are uncommon. They are secondary to trauma, rupture of great vessels or heart and associated to iatrogenic events. We report a case of a 61 year-old woman who consults for mediastinal hematoma without previous trauma. Imaging studies ruled out cardiac or vascular lesions. At exploratory thoracotomy, a large mediastinal hematoma was evidenced without obvious mass or bleeding vessel. The material sent to the Pathology service was diagnosed as cystic adenoma of ectopic parathyroid gland. Mediastinal hematomas are related to traumatic causes, cardiac or great vessels rupture or iatrogenic proceedings. Once these causes are ruled out, an injury of ectopic parathyroid tissue must be considered in the differential diagnosis because mediastinum is the most frequent ectopic location. Histopathological and immunohistochemical studies are useful in determining the cause-related hematoma, as in this case determined the parathyroid origin of the lesion, and to rule out involvement by other tumors.

[Colonic metastases of breast infiltrating lobular carcinoma: atypical presentation of a clinical case]. / Carcinomatosis colónica por carcinoma lobulillar de mama: presentación inusual de un caso.

Gastrointestinal metastases are rare. May occur years after initial diagnosis and its symptoms are nonspecific, delaying its correct diagnosis and aggravating its prognosis. The most common histological subtype is lobular breast carcinoma. We present a 75-year-old woman with history of left mastectomy six years ago by infiltrating lobular carcinoma. She was treated with tamoxifen for five years. At present, there was no evidence of disease. She attended the hospital for intestinal subocclusion, being admitted for study. A barium enema revealed multiple strictures of the large bowel and a colonoscopy revealed an impassable stricture in the rectum-sigma. Due to the severity of symptoms, underwent total colectomy. The suspected diagnosis was Crohn's disease. The surgical specimen showed multiple stenosis of the light, with thickened wall and mucosa with granulations. Microscopic examination showed transmural infiltration of colonic wall by malignant cells CK7 positive and ER positive. Breast infiltrating lobular carcinoma has more special tendency to affect the digestive tract, even many years after the diagnosis of the primary tumor. In front of a patient with history of breast cancer and gastrointestinal symptoms, its mandatory to consider gastrointestinal metastases, making differential diagnosis with inflammatory bowel disease, infections or primary tumors, as the therapeutic actions are different.

[Granulomatous peritonitis due to the starch used in surgical gloves]. / Peritonitis granulomatosa por el almidón en guantes quirúrgicos.

Granulomatous peritonitis due to surgical glove starch is an entity of difficult diagnosis and low incidence. Patients present with abdominal pain, fever and prolonged functional ileus three to four weeks postoperatory of a laparotomy where corn starch as glove's lubricant had been used. In surgical re-exploration both the peritoneum and omentum are widely affected with multiple small white nodules together with peritoneal fluid. Histopathology shows inflammatory tissue with giant multinucleated cells containing bi-refringent cornstarch particles inside. Under polarized light the typical maltese cross appearance of cornstarch is revealed. We present a 54 year old woman admitted with abdominal pain, fever and an unusually prolonged ileus in postoperatory period after a laparotomy. Conventional hysterectomy was performed three months before. At admission, exploratory videolaparocopy was done, in which accidentally distal jejunum was perforated which required laparotomy for enterorraphy. One month after she was re-laparotomized due to persistence of ileus. Granulomatous peritonitis was evidenciated and confirmed by histopathology. Endovenous hydrocortisone was given during two weeks and shifted to oral prednisone during four weeks with gradual diminution until suppression. Patient is asymptomatic at seven months of postoperatory. Corticosteroid treatment is an efficient choice. The prevention is crucial and is based on the employment of starch free surgical gloves.

Kikuchi-Fujimoto disease and systemic lupus erythematosus.

Kikuchi-Fujimoto disease, or histiocytic necrotizing lymphadenitis, is an infrequent idiopathic disorder. It has been associated with autoimmune disorders, of which systemic lupus erythematosus is the most outstanding. The basis of its diagnosis relies on the histological examination of lymph nodes, which typically reveals necrosis surrounded by histiocytes with crescentic nucleus, immunoblasts and plasma cells, and absence of neutrophils. We report the case of a 27-year-old Argentinian female patient without any relevant past medical history to demonstrate the correlation between Kikuchi-Fujimoto disease and systemic lupus erythematosus.

Lack of TNFRI signaling enhances annexin A1 biological activity in intestinal inflammation.

We evaluated whether the lack of TNF-α signaling increases mucosal levels of annexin A1 (AnxA1); the hypothesis stems from previous findings showing that TNF-α neutralization in Crohn's disease patients up-regulates systemic AnxA1 expression. Biopsies from healthy volunteers and patients under anti-TNF-α therapy with remittent ulcerative colitis (UC) showed higher AnxA1 expression than those with active disease. We also evaluated dextran sulfate sodium (DSS)-acute colitis in TNF-α receptor 1 KO (TNFR1-/-) strain with impaired TNF-α signaling and C57BL/6 (WT) mice. Although both strains developed colitis, TNFR1-/- mice showed early clinical recovery, lower myeloperoxidase (MPO) activity and milder histopathological alterations. Colonic epithelium from control and DSS-treated TNFR1-/- mice showed intense AnxA1 expression and AnxA1+ CD4+ and CD8+ T cells were more frequent in TNFR1-/- animals, suggesting an extra supply of AnxA1. The pan antagonist of AnxA1 receptors exacerbated the colitis outcome in TNFR1-/- mice, supporting the pivotal role of AnxA1 in the early recovery. Our findings demonstrate that the TNF-α signaling reduction favors the expression and biological activity of AnxA1 in inflamed intestinal mucosa.

Early inflammatory markers in elicitation of allergic contact dermatitis.

BACKGROUND: Allergic Contact Dermatitis (ACD) is regarded as a T-cell-mediated delayed-type hypersensitivity reaction. We studied the kinetics of the expression of CS-1 fibronectin, thymus and activation-regulated chemokine (CCL17/ TARC) and different chemokine receptors (CR) in skin biopsies from individuals suffering from back problems, with the antigen responsible of their contact dermatitis and an irrelevant antigen. METHODS: Samples were taken at 2, 10, and 48 hours for histological and immunohistochemical studies using monoclonal antibodies against human CS-1 fibronectin, CCL17, CD3, CD68, CD49d, CXCR3, CCR5, and CCR3. RESULTS: At positive antigen stimulated sites there was an early expression of CS-1 fibronectin (2 hours), followed by CCL17 and a later accumulation of alplha4/beta1+ (CD49d), CD3+, CD68+, CXCR3+ and CCR5+ mononuclear cells. At 48 hours, approximately 59 % of infiltrating cells were CXCR3+, 42% CCR5+, and only 14 % CCR3+. CONCLUSIONS: These results showed for the first time a very early expression of CS-1 fibronectin which preceded production of CCL17 in blood endothelial cells (BCEs) from patients' skin with ACD. The role of these molecules in recruitment of monocytes and effector T cells in ACD is discussed.

[Extranodal NK/T cell lymphoma of the nasal type]. / Linfoma de celulas NK/T Extranodal tipo nasal.

The vast majority of lymphoma occurring in the testis are diffuse large B-cell Lymphoma. We report on a case of natural killer/T cell lymphoma in a forty four year old male, with bilateral testicular and cutaneous involvement with a highly aggressive course. The tumor cells were positive for both CD56 and Epstein Barr Virus, encoded EBER molecules, and showed focal angiocentric growth thus fullfilling the criteria for NK/T cell lymphoma of nasal type. Dermatopathologists and uropathologists should be aware of this rare entity which may only be diagnosed after extensive inmunohistochemical studies.

Expression of VEGF-A, HIF-1 A, CD34 and Ki67 in clear cell renal cell carcinomas and their relationship with conventional prognostic markers.

Clear cell renal carcinoma is the most frequent type of renal carcinoma. Recently, attention has been focused in the expression of angiogenic factors by these tumors, which would justify in part their capacity to grow, invade and disseminate, stating a worse evolution of those patients with an unfavorable angiogenic profile. 83 samples of nephrectomy with a diagnosis of clear cell renal cell carcinoma were studied. Clinical and pathological data were collected. Tumors were studied to assess immunohistochemical expression of the following markers: VEGF-A, HIF-1α, CD34 and Ki67. Results indicated a direct linear relationship between expressions of these four markers. Besides, the expression of HIF-1α was directly related to Furhman grade, invasion of the renal vein and tumor stage. Likewise, tumor proliferation index, assessed with Ki67, was directly related to the presence of necrosis, capsular invasion and advanced tumor stage. Regarding the expression of CD34, vascular density was inversely related to tumor necrosis and overall survival. These findings are controversial compared with the available literature. Then, a research scenery would be open, where the importance of generating prospective and more standardized studies are highlighted to determine the role of these angiogenic factors in tumor evolution and prognostic evaluation of these tumors.

El carcinoma renal de células claras es la variante más frecuente de carcinoma renal. En los últimos años, la atención se ha enfocado en la expresión de factores angiogénicos por estos tumores, lo que justificaría en parte su capacidad de crecer, invadir y diseminarse, determinando una peor evolución de aquellos pacientes con un perfil angiogénico desfavorable. Se estudiaron 83 piezas de nefrectomía con diagnóstico de carcinoma renal de células claras. Se recolectaron datos clínicos y patológicos. Los tumores fueron estudiados para evaluar la expresión inmunohistoquímica de los siguientes marcadores: VEGF-A, HIF-1α, CD34 y Ki67. Los resultados indicaron una relación lineal directa entre la expresión de estos cuatro marcadores. Además, la expresión de HIF-1α se encontraba directamente relacionada con el grado de Furhman, la invasión de la vena renal y el estadio tumoral. Asimismo, el índice de proliferación tumoral, evaluado con Ki67, se hallaba directamente relacionado con la presencia de necrosis, la invasión capsular y el estadio tumoral avanzado. Con respecto a la expresión de CD34, mientras mayor es la densidad vascular, menor es la necrosis tumoral y menor la sobrevida global. Los hallazgos resultan controvertidos en comparación con la literatura disponible. Se abriría, entonces, un escenario de investigación donde se destaca la importancia de generar estudios prospectivos y más estandarizados para determinar el rol que cumplen estos factores angiogénicos en la evolución tumoral y la posibilidad de estandarizar resultados que permitan un mejor estudio diagnóstico y pronóstico de estos tumores.

[Undifferentiated high grade pleomorphic sarcoma/ malignant fibrous histiocytoma associated a gouty tophus. a case report]. / Sarcoma pleomórfico indiferenciado de alto grado/ fibrohistiocitoma maligno asociado a tofo gotoso. presentación de un caso.

BACKGROUND: Gout is a metabolic disease by deposition of uric acid crystals, which undertakes joint and soft tissue in both acute and chronic stages. Is a rare event the onset of a tumor in the site of the lesion. OBJECTIVE: To present a rare case of association between sarcoma and tophi. METHODS: 83 year old man who consulted for tumor in his left elbow about 40 years of evolution, which spontaneously started to hurt. With the presumptive diagnosis of tophi treated surgically. The lesion recurred after 60 days, reintervention and radiotherapy was performed for diagnosis of malignant mesenchymal tumor associated with tophi. At 10 months developed ipsilateral nodal metastases, died within 2 years of the initial consultation. RESULTS: The diagnosis of the first material resected was tophi. In the reintervention material was diagnosed mesenchymal spindle cell high grade neoplasm associated with tophi; immunohistochemistry revealed: vimentin + / +, MYO D1 - / - ASMA - / -, FVIII - / -, A1ATT - / -, CD68-/ -, S100-/ - with final diagnosis the undifferentiated high grade pleomorphic sarcoma. CONCLUSIONS: It is uncommon for gouty tophi are associated with other diseases and even fewer do so to tumors. In the literature have reported three previous cases concurrent with neoplasms, which were angiosarcoma, giant cell tumor and malignant fibrous histiocytoma. The latter have a high tendency to recur locally and have ability to distant metastases, especially lung and regional lymph nodes.

Antecedentes: La gota es una enfermedad metabólica por depósito de cristales de ácido úrico, que compromete articulaciones y tejidos blandos tanto en sus etapas agudas como crónicas. Constituye un suceso poco común la aparición de un tumor en el sitio propio de la lesión. Objetivo: presentar un caso de asociación infrecuente entre tofo gotoso y sarcoma. Material y métodos: hombre de 83 años que consultó por tumoración en codo izquierdo de aproximadamente 40 años de evolución, que comenzó a doler espontáneamente. Con la presunción diagnóstica de tofo gotoso se trató quirúrgicamente. La lesión recidivó a los 60 días, se realizó reintervención y radioterapia por diagnóstico de tumor mesenquimal maligno asociado a tofo gotoso. A los 10 meses desarrolló metástasis ganglionar homolateral, falleció antes de los 2 años de la consulta inicial. Resultados: El diagnóstico de la primer biopsia fue tofo gotoso. En el material de reintervención se diagnosticó tofo gotoso asociado a neoplasia mesenquimal fusocelular de alto grado; la inmunohistoquímica reveló: vimentina +/+, MYO D1 -/-, ASMA -/-, FVIII -/-, A1ATT -/-, CD68-/-, S100-/- con resultado diagnóstico final de sarcoma pleomórfico indiferenciado de alto grado. Conclusión: Es infrecuente que los tofos gotosos se asocien a otras enfermedades y menos que lo hagan a tumores. En la bibliografía se han reportado tres casos previos concurrentes con neoplasias, las cuales fueron angiosarcoma, tumor de células gigantes y fibrohistiocitoma maligno. Estos últimos tienen una alta tendencia a recidivar y poseen capacidad de dar metástasis, especialmente a pulmones y ganglios regionales. Palabras clave: tofo gotoso, fibrohistiocitoma maligno, sarcoma pleomórfico indiferenciado.

Tumor del estroma gastrointestinal y trasplante renal / Gastrointestinal stromal tumor and renal transplant

El tumor estromal gastrointestinal (GIST) representa alrededor del 1% de todos los tumores digestivos y su aparición en pacientes trasplantados renales es infrecuente. Aproximadamente el 95% muestra tinción positiva para c-kit/CD117. DOG1 es un anticuerpo recientemente descrito que se sobre-expresa en los GIST, incluso en c-kit/ CD117 negativos. El diagnóstico preciso de GIST resulta imperativo, debido a la disponibilidad y la creciente eficacia de los inhibidores de la tirosina quinasa en estos tumores, incluso en el subgrupo c-kit/ CD117 negativo. Se presenta el caso de una mujer trasplantada renal inicialmente con GIST en intestino delgado y débil positividad para CD117 tratada con cirugía y recidiva tumoral a los tres años, pérdida de la expresión CD117 y tinción positiva para DOG1. Recibió tratamiento exitoso con imatimib sin presentar recaída tumoral durante un seguimiento de cinco años.

Gastrointestinal stromal tumor (GIST) accounts for nearly 1% of all gastrointestinal tumors. Its association with renal transplantation is not frequent. Approximately 95% of GIST show staining for CD177. DOG1 is a recently described monoclonal antibody that shows positivity even in the absence of CD177 staining. The diagnosis of GIST should be pursued because of the availability of very effective treatments with tyrosine-kinase inhibitors. Herein, we describe the case of a woman with renal transplant who presented a small bowel GIST and weak positivity for CD177, treated initially with surgery. Tumor recurrence was documented 3 years later and histopatology showed loss of CD177 staining and positivity for DOG1. She was treated with imatimib without further recurrence after five years of follow up.

[Primary hydatid disease of the tibia. case report]. / Hidiatidosis osea primaria de tibia: presentación de un caso.

Hydatidosis is an endemic disease in different parts of the world. Its causal agent is the cestode from the genus Echinococcus. The most commonly affected organs in humans are liver and lung. Bone hydatid disease is a very rare entity, accounting for 0.5 to 4% of total cases. We report a case of a 58 year-old woman from La Rioja, Argentina, who consulted for left infapatellar pain and walking disability of eight months duration. Imaging studies showed a cystic lesion which involved metaphysis and diaphysis of left proximal tibia. Surgical resection was performed and histopathological study confirmed that it was a hydatid cyst. The patient did well and completed three cycles of treatment with albendazole. Currently, she has no evidence of disease and she recovered motility of her left leg. Primary hydatid bone disease, where there is no evidence of systemic disease, is even more unusual. Tibia involvement occurs in up to 15% of the cases. These lesions clinically manifest when they suffer any type of complications. Preoperative diagnosis is mainly made by imaging studies. Lesions are usually osteolytic and can involve cortical bone and extend to soft tissues. Differential diagnosis with inflammatory processes and bone tumors should is mandatory. Treatment is surgical and prognosis is poor due to its high morbi-mortality rate and recurrence risk from 70 to 80%.