An unusual renal malignancy of childhood: unilateral teratoid Wilms's tumor.

Teratoid Wilms's tumor is a rare histologic variant of the classical Wilms's tumor, containing predominantly heterolougus tissues (adipose, glial, muscle, cartilage, or bone). We report an unusual variant of such tumor, which simulated renal teratoma because of abundant fat within the tumor. The child underwent radical excision; postoperatively, he was treated with chemotherapy, and now the child is well at 36 months after surgery. The behavior of this kind of tumor usually is not aggressive, and the outcome is good. Surgery should be the treatment of choice, because the efficacy of chemotherapy and radiotherapy is probably reduced by the high amount of differentiated and mature tissue that characterizes this neoplasm. Radiologic imaging and pathological features of this rare entity are described.

High-resolution CT in renal transplant patients with suspected pulmonary infections.

OBJECTIVE: This prospective study was carried out to assess the usefulness of high-resolution CT (HRCT) of the chest in immunocompromised renal transplant patients with suspected pulmonary infections. MATERIAL AND METHODS: Twenty-one consecutive renal transplant patients with clinically suspected pulmonary infections underwent chest radiography, HRCT and other tests including bronchoalveolar lavage (BAL). HRCT was performed using a high spatial frequency algorithm with 2-mm-thick sections at 10-mm intervals from apices to domes of the diaphragm. The findings on chest radiography and HRCT were interpreted by two thoracic radiologists and the usefulness of HRCT was evaluated. The images were interpreted independently by two radiologists, who were blinded to the findings of other imaging modalities and the final diagnosis. Any differences regarding the imaging findings were resolved through consensus. RESULTS: Final diagnosis was obtained in 17 patients, and no cause for symptomatology was established in 4 patients. The spectrum of infections included pulmonary tuberculosis (TB) in 11 patients, cytomegalovirus pneumonia (CMV) in 2 patients, cryptococcal and streptococcal pneumonia, pulmonary aspergillosis and esophageal candidiasis in 1 patient each. Compared to chest radiography, HRCT revealed additional findings in 11 patients. HRCT findings were suggestive of underlying infection in 11 patients. The final diagnosis coincided with HRCT diagnosis in all but 1 patient. HRCT findings were non-specific in 3 patients and normal in 7. The findings were concordant in 19 cases. The results were not in agreement in only 2 cases. CONCLUSION: HRCT can provide useful information and suggest the diagnosis in a significant proportion of renal transplant patients with pulmonary infection.

Ultrasound guided fine needle aspiration biopsy in mediastinal tuberculosis.

SETTING: Diagnosis of mediastinal tuberculosis (TB) is difficult due to non-specific clinical features and lack of characteristic radiographic features. Histopathological confirmation has often required computed tomography guided fine needle aspiration biopsy (FNAB) or even invasive procedures such as mediastinoscopy or open/surgical biopsy. FNAB under ultrasound (US) guidance can also be performed in this clinical setting. OBJECTIVE: To define the role of percutaneous US guided FNAB in the diagnosis of mediastinal tuberculosis. DESIGN: Twenty-six patients with a proven diagnosis of mediastinal TB formed the study group. Chest radiographs and sputum examination were negative. FNAB was performed via suprasternal (n = 20) and parasternal (n = 6) route under sonographic guidance using 22G spinal needle. Aspirates were considered positive for TB when epithelioid cell granuloma with caseation necrosis and/or the presence of Mycobacterium tuberculosis by acid-fast bacilli (AFB) or culture was demonstrated, indeterminate when epithelioid cell granulomas were seen but without caseation necrosis or AFB, and negative when aspirate contained non-representative material. RESULTS: A total of 30 biopsies were performed in the 26 patients, including repeat biopsy and biopsy of different sites in two patients each. FNAB was positive for TB in 20 of the 26 patients. In four, AFB were demonstrated, and in seven culture was positive for M. tuberculosis; in the remaining six patients, cytologic diagnosis was indeterminate in four and negative in two. No procedure related complications were noted. CONCLUSION: Ultrasound guided FNAB is a safe, effective technique in the diagnosis of mediastinal TB.

Comparative evaluation of plain films, ultrasound and CT in the diagnosis of intestinal obstruction.

BACKGROUND: There are limited studies in the literature comparing plain radiography, US and CT in the evaluation of intestinal obstruction. We carried out this prospective study to compare the relative efficacies of these three imaging techniques in patients with intestinal obstruction. MATERIAL AND METHODS: Thirty-two patients presenting with clinical suspicion of intestinal obstruction were subjected to plain radiography, US and CT and the findings were compared with reference to the presence or absence of obstruction, the level of obstruction and the cause of obstruction. The final diagnosis was obtained by surgery (n=25), or by contrast studies and/or clinical follow-up in those who were treated conservatively (n=7). RESULTS: Out of 32 patients, 30 had mechanical intestinal obstruction (22 had small bowel obstruction and 8 had large bowel obstruction). Of the remaining 2 patients, 1 had adynamic ileus and the other had a mesenteric cyst. CT had high sensitivity (93%), specificity (100%) and accuracy (94%) in diagnosing the presence of obstruction. The comparable sensitivity, specificity and accuracy were, respectively. 83%, 100% and 84% for US and 77%, 50% and 75% for plain radiography. The level of obstruction was correctly predicted in 93% on CT, in 70% on US and in 60% on plain films. CT was superior (87%) to both US (23%) and plain radiography (7%) in determining the aetiology of obstruction. CONCLUSION: CT is a highly accurate method in the evaluation of intestinal obstruction especially for determining the level and cause of obstruction and should be the technique of choice when clinical or plain radiographic findings are equivocal.

Ultrasound-guided fine needle aspiration biopsy of gall bladder malignancies.

PURPOSE: To establish the safety and efficacy of US-guided fine needle aspiration biopsy (FNAB) in gall bladder malignancies. MATERIAL AND METHODS: 142 patients suspected to have gall bladder malignancies underwent FNAB under real-time US guidance. The most common sonographic appearances were a mass filling or replacing the gall bladder (n=98), focal or diffuse wall thickening (n=25) and intraluminal polypoidal mass (n=19). FNAB was performed with a 0.7-mm spinal needle using a free-hand technique. RESULTS: On initial FNAB, 115 patients were diagnosed to have malignancy. In the remaining 27 patients, aspirates on first FNAB showed either inflammatory pathology (n=14) or the sample was suspicious of malignancy (n=7), or the aspirates were non-representative (n=6). Of these 27 patients, 13 underwent repeat FNAB because of the high suspicion of malignancy and 12 of them showed malignancy. The FNAB diagnosis of inflammatory disease of 7 patients was confirmed on subsequent surgery and 8 patients were lost to follow-up. Thus, a total of 127/142 were diagnosed to have gall bladder malignancy. Adenocarcinoma was the most common malignancy (89.76%). No procedure-related complications were encountered. CONCLUSION: US-guided FNAB is a safe and accurate technique to diagnose gall bladder malignancy. Either a repeat FNAB or surgical biopsy is recommended when the suspicion of malignancy is high and the initial FNAB is negative.

Ultrasound guided fine needle aspiration biopsy of splenic lesions.

Fine needle aspiration biopsy (FNAB) of focal splenic lesions has been infrequently utilized because of the risk of haemorrhage. This study was carried out to evaluate the safety and efficacy of ultrasound guided FNAB of splenic lesions. 35 patients with focal splenic lesions underwent FNAB under real-time ultrasound guidance using a free hand technique. Ultrasound findings were single or multiple focal hypoechoic lesions (n = 33), focal hyperechoic lesion (n = 1) and diffuse heterogeneous echotexture (n = 1). Aspirations were performed with 22 G spinal needles using either the subcostal or the intercostal approach. Definite cytological diagnosis was made in 22 patients (62.8%), including tuberculosis in 10 patients, lymphoma in seven patients, extramedullary haematopoiesis in two patients and aspergillosis, histoplasmosis and bacterial abscess in one patient each. FNAB was negative in 12 patients because the aspirates were either scanty or contained only blood. FNAB was falsely positive in one patient. Only one patient had significant intraabdominal bleeding, which was managed conservatively. In conclusion, splenic FNAB performed under ultrasound guidance is a safe and accurate method in the diagnosis of focal splenic lesions.