Glomus coccygeum: a review.

With limited information about the coccygeal glomus found in classic textbooks, we deemed it necessary to review the subject. The illustrations presented in this article derive from four coccygeal glomera incidentally encountered during examination of pilonidal disease specimens. Familiarization with its microanatomical features may help to avoid inappropriate interpretation of this enigmatic structure.

Quantitation of nitrotyrosine levels in lung sections of patients and animals with acute lung injury.

Activated alveolar macrophages and epithelial type II cells release both nitric oxide and superoxide which react at near diffusion-limited rate (6.7 x 10(9) M-1s-1) to form peroxynitrite, a potent oxidant capable of damaging the alveolar epithelium and pulmonary surfactant. Peroxynitrite, but not nitric oxide or superoxide, readily nitrates phenolic rings including tyrosine. We quantified the presence of nitrotyrosine in the lungs of patients with the adult respiratory distress syndrome (ARDS) and in the lungs of rats exposed to hyperoxia (100% O2 for 60 h) using quantitative immunofluorescence. Fresh frozen or paraffin-embedded lung sections were incubated with a polyclonal antibody to nitrotyrosine, followed by goat anti-rabbit IgG coupled to rhodamine. Sections from patients with ARDS (n = 5), or from rats exposed to hyperoxia (n = 4), exhibited a twofold increase of specific binding over controls. This binding was blocked by the addition of an excess amount of nitrotyrosine and was absent when the nitrotyrosine antibody was replaced with nonimmune IgG. In additional experiments we demonstrated nitrotyrosine formation in rat lung sections incubated in vitro with peroxynitrite, but not nitric oxide or reactive oxygen species. These data suggest that toxic levels of peroxynitrite may be formed in the lungs of patients with acute lung injury.

Diagnostic histopathologic criteria in pediatric tumors: an eclectic review.

Malignant tumors of infants and children, unlike their adult counterparts, are commonly undifferentiated or show minimal evidence of differentiation. Because of this, many of these tumors pose a formidable dilemma to the general pathologist in distinguishing one from another. A broad sampling of the more common malignant neoplasms and of newly recognized histologic subtypes which are restricted more or less to the pediatric age group is presented. The minimal microscopic criteria required to establish a diagnosis are given using widely accepted pathologic classifications and seminal journal references as a guide. Ancillary microscopic features, helpful histochemical stains, immunohistochemistry, and ultrastructural morphology are described for most tumors. Histologic distinction from diagnostic mimickers is discussed. Where appropriate, histologic grading and tumor subclassification are presented and their prognostic relevance is reviewed.

Local complications associated with indwelling Swan-Ganz catheters: autopsy study of 36 cases.

Thirty-six hearts of patients who died with indwelling Swan-Ganz catheters in place were prospectively examined to assess the incidence and extent of localized lesions in the right side of the heart. Bland mural thrombosis in the superior vena cava, the right atrium and the pulmonary artery was found in 22 of 36 cases (61%). Patients with catheter periods greater than 2 days had a greater incidence and extent of bland mural thrombosis (79%) than patients with short-term catheterization (41%, p less than 0.01). Anticoagulation had no influence on bland mural thrombosis. Valvular hemorrhage occurred in 31% and aseptic valvular vegetations in 8% of the hearts. No case of infective endocarditis was found. Four of 36 cases (11%) had evidence of pulmonary infarction that appeared to be unrelated to the lesions in the right side of the heart. Endocardial lesions were common complications of indwelling Swan-Ganz catheters but had no significant impact on the clinical courses of the patients.

Physical and mechanical effects of cardioplegic injection on flow distribution and myocardial damage in hearts with normal coronary arteries.

The physical and mechanical effects of injecting crystalloid cardioplegic solution under various pressures and flows was studied (in canine hearts) to establish a safe method for administering it in the presence of normal coronary arteries. A constant pressure system (300 mm Hg = 15 psi) was maintained in the solution reservoir, and flows and pressures were varied with the use of cannulas of different inner diameters: 0.8, 1.35, 1.6, 2.3, 2.58, and 2.80 mm. Cardioplegia distribution was measured by 15 microns radioactive microspheres. Peak flow rate, total flow, and mean flow rate per infusion were measured by an inline electromagnetic flowmeter probe. Direct aortic root pressure, time to standstill, and myocardial temperatures were recorded by continuous monitoring. Cardiac isoenzymes were measured in the coronary sinus, peripheral blood, and directly in the myocardial tissue. Histologic changes in the left ventricle were examined by light microscopy. The results showed that the higher the flow and pressure, the shorter the prearrest period, the better the flow distribution, and the faster the myocardial temperature drop. Mean aortic root pressures higher than 110 mm Hg and peak flow rates greater than 1500 ml/min caused a higher incidence of mechanical-physical trauma to the vascular endothelium and the endocardium, but cellular protection was good. Low pressure (less than 30 mm Hg) and peak flows (less than 125 ml/min) showed a higher incidence of cellular (myocardial) ischemia, focal necrosis, and uneven flow distribution. An aortic root pressure of 61 +/- 5 mm Hg, a mean peak flow rate of 622 +/- 52 ml/min, and a total flow of 600 ml for the first injection seem to offer the best cellular protection with minimal physical injury to the endothelium and endocardium for a mean canine heart weight of 236 gm.

Changes of hepatoma echo patterns with tumor growth. A study of the microanatomic basis in a rat model.

OBJECTIVES: The echo patterns of human hepatoma vary considerably as the tumors grow. This sonographic study investigates the microanatomic basis of the echo-pattern changes in an animal model. METHODS: ACI rats (n = 35) with intrahepatically implanted Morris hepatoma 3924A were imaged with 10-MHz ultrasound from days 7 to 28 after tumor implantation. The sonograms were precisely correlated with the histologic sections and microangiograms obtained from the same section plane. RESULTS: Small hepatomas (size = 6.6 +/- 1.6 mm) without necrosis demonstrated a low-echo pattern. Medium-sized tumors (size = 11.7 +/- 3.3 mm) had a low-echo periphery and a high-echo center. The low-echo periphery corresponded to viable tumor and the high-echo core corresponded to central coagulation necrosis. Large tumors (size = 20.9 +/- 7.5 mm) with extensive necrosis revealed an irregular mixed-echo pattern. CONCLUSIONS: The trend of increasing echogenicity of the hepatomas with tumor growth is due to the progression of coagulation necrosis.

Extracorporeal liver ablation using sonography-guided high-intensity focused ultrasound.

RATIONALE AND OBJECTIVES: High-intensity focused ultrasound (HIFU) is the only radiation beam that can remotely destroy deep-seated tissue targets without causing damage to the intervening tissues. This study evaluates the ability of sonography-guided HIFU to extracorporeally induce liver ablation in a rabbit model. METHODS: Under sonographic guidance, the HIFU beam was transcutaneously focused at the target tissue in the liver through a subcostal approach. A computer controlled the HIFU exposure and transducer movement to destroy a preselected tissue volume. Simultaneous sonography monitored the tissue response. Ten insonated rabbits were killed from days 0 to 10, and the liver and intervening tissues were examined histologically. RESULTS: A sharply demarcated sonolesion of coagulation necrosis was produced in the liver in 9 of 10 animals. No damage was found in the intervening tissues (n = 6) when adequate acoustic coupling and proper beam path was applied. CONCLUSION: Sonography-guided HIFU might be a potential new modality for extracorporeal inducement of liver cancer ablation without resorting to laparatomy.

Sonographic and computed tomography characteristics of liver ablation lesions induced by high-intensity focussed ultrasound.

RATIONALE AND OBJECTIVES: The authors have previously demonstrated the ability of high-intensity focused ultrasound (HIFU) to extracorporeally induce selective tissue destruction in the liver without causing damage to the intervening abdominal wall. The potential usefulness of HIFU as a noninvasive therapy for liver cancer has been suggested. This study observes sonographic and computed tomography (CT) characteristics of HIFU-ablated liver tissue in an attempt to assess the possibility of using these imaging methods to monitor the therapeutic results. METHODS: A sonoablated lesion was induced in the liver in each of 20 rabbits with a HIFU therapeutic system. Sequential imaging of the hepatic sonolesions with sonography and CT was performed up to 8 days after treatment, and the imaging patterns were correlated with the histopathology. RESULTS: Hepatic sonoablated tissue could be clearly visualized by sonography as a hypoechoic lesion. On contrast-enhanced CT, the sonolesions were depicted as nonenhanced low-density regions. There was good correlation among the sizes of sonography- and CT-depicted lesions and pathologic specimens. CONCLUSION: In this model, sonography and contrast-enhanced CT were useful imaging modalities for monitoring sonolesion evolution after HIFU treatment.

Pigmented cardiac paraganglioma.

A pigmented left atrial paraganglioma was found at autopsy in a 40-year-old black man who died unexpectedly. The cause of death was ascribed to coronary artery disease. The atrial mass was sharply demarcated and polypoid, measured 4 cm in greatest dimension, and had a cut surface that revealed dark red-brown soft tumor tissue. Histopathologically, the neoplasm exhibited a classic organoid clustering of cells (zellballen) with a prominent capillary network. The chief cells contained a brown-black pigment with histochemical characteristics of melanin. We report a case of pigmented cardiac paraganglioma because of its rarity. To our knowledge, no mention has been made of the presence of pigment in previously reported cases of cardiac paragangliomas.

Alpha 1-antitrypsin deficiency in a child with X-linked lymphoproliferative disease.

An 18-month-old white male infant with X-linked lymphoproliferative disease was evaluated for persistent hepatic dysfunction following primary Epstein-Barr virus infection. A liver biopsy revealed cirrhosis with a dense mononuclear cell infiltrate. These findings were confounding because cirrhosis is not a typical finding in either normal or immunodeficient individuals following infection with Epstein-Barr virus. An alpha 1-antitrypsin level obtained shortly after biopsy was spuriously within the lower limits of the physiologic range. Further investigation demonstrated a homozygous Z phenotype, the classic protease inhibitor variant described in alpha 1-antitrypsin deficiency. A repeat liver biopsy confirmed the presence of a second hereditary disease. This is a unique concurrence of two uncommon genetic disorders.

Congenital pyloric atresia and junctional epidermolysis bullosa: a report of long-term survival and a review of the literature.

The coexistence of congenital pyloric atresia (PA) and epidermolysis bullosa (EB) in newborns is a rare but distinct association. Mortality is high. In particular, a universally fatal outcome has been reported in neonates born with the junctional type of EB and PA. This has led some investigators to advocate that surgical correction of PA be withheld to obviate needless suffering. We treated five patients, including one set of siblings. Maternal hydramnios and nonbilious vomiting were constant features. Delayed passage of meconium was found in four. Plain x-rays demonstrated gastric dilatation in an otherwise gasless abdomen. Blistering skin lesions were noted at birth in four and developed soon after in the last patient. All lesions were determined to be junctional EB based on electronmicroscopy. The clinical course for these children has been far better than the literature predicts. Successful repair of PA was performed after appropriate stabilization. One infant died at 4 months of age of staphyloccal septicemia, malnutrition, and sepsis from chronic urinary tract obstruction. Another child, born with dysmorphic features to consanguineous parents, is 9 years old and has a seizure disorder. The remaining three are alive and well at 17 months, and 9 and 16 years. The oldest two are siblings. In all four surviving patients, the blistering nonscarring lesions were found to significantly improve in severity, duration, and occurrence with age. Presently, these lesions are mild and require little therapy. Their nails, initially normal at birth, have become discoloured, thickened, and dystrophic. The management of pitted, carious, and yellow teeth is currently the major problem.(ABSTRACT TRUNCATED AT 250 WORDS)

Neuroblastoma invading the kidney.

Renal invasion by neuroblastoma is probably more common than is generally recognized. In this study, the incidence of renal parenchymal tumor invasion was 20.4% (10 patients) among 49 cases of abdominal neuroblastoma. Generally, the renoinfiltrative neuroblastomas were extensive and had unfavorable histological features as well as lymph node involvement; they were either stage III or IV. Tumor invasion occurred by direct penetration through the renal capsule and/or lymphatic perivascular spread. Imaging studies had 100% sensitivity and 94.9% specificity for detecting renal invasion of neuroblastoma. Surgery/pathology was the standard of reference. Two instances of misdiagnoses of renal invasion were attributed to inadequate resolution of older computed tomography films, partial volume effects, and renal distortion by tumor compression.

Early use of cisplatin is safe after partial hepatectomy.

Although cisplatin is widely used in the treatment of liver tumors, little information is available concerning its effect on liver regeneration. This report evaluates the effect of cisplatin on liver regeneration after hepatectomy (HPx). One hundred sixty male Sprague-Dawley rats were placed into five experimental groups following 70% hepatectomy. Group I (untreated controls, n = 32) received 0.9% saline intraperitoneally (IP); group II (n = 31), cisplatin 4 mg/kg IP; group III (n = 36), cisplatin 10 mg/kg IP; group IV (n = 34), cisplatin 20 mg/kg IP; and group V (n = 27), doxorubicin 6 mg/kg intravenously (IV). Five additional sham groups underwent celiotomy without hepatectomy (n = 106) followed by the above treatment protocols. Liver regeneration was evaluated by liver weight, DNA incorporation measured by tritiated thymidine (3H-TdR), and quantitative image analysis (QIA) of hepatic nuclei at 18, 24, 36, 48, and 72 hours, and 5 days postoperatively. 3H-TdR incorporation peaked at 36 hours and was similar in hepatectomized controls group I (404 +/- 110 counts per minute [CPM]/mg liver weight) and cisplatin-treated rats (groups II to IV) (P > .05, ANOVA). All sham groups were similar to controls. QIA of feulgen-stained touch preps identified polyploid, stem line, and proliferating nuclei in both controls and treated groups. At 36 hours, QIA showed differences in mitotic status of sham, control, and adriamycin-treated HPx rats, consistent with 3H-TdR incorporation. In contrast, although cisplatin-treated rats receiving 4 mg/kg showed proliferating nuclei, QIA demonstrated decreasing hepatocyte proliferation with higher doses of cisplatin (10 mg/kg, and 20 mg/kg).(ABSTRACT TRUNCATED AT 250 WORDS)

Pharyngeal fibrovascular polyp in a child.

Fibrovascular polyp of the upper aerodigestive tract is an uncommon tumor that may present in pediatric patients with symptoms ranging from dysphagia to asphyxiation and death. We present a unique case of a pediatric patient with an asymptomatic fibrovascular polyp noted as an incidental finding on a cervical ultrasound evaluation. This lesion extended from the posterior tonsillar pillar and prolapsed freely into the nasopharynx and esophagus. The literature relevant to this case is reviewed, and the etiology, pathophysiology, and management principles are discussed.

Laryngomalacia and intra-neural striated muscle in an infant with the Freeman-Sheldon syndrome.

Striated muscle cells within peripheral nerve trunks, a very rare dishistogenetic lesion, was found in the arytenoid submucosa of a ten and a half week old afroamerican male with the Freeman-Sheldon syndrome (craniocarpotarsal dysplasia) who presented with obstructive apnea. Laryngomalacia was confirmed endoscopically. Supraglottoplasty offered temporary relief of the obstruction. Our histopathological observation is puzzling and perhaps adds a new dimension to the appropriateness of 'dysplasia'. It remains to be seen whether the neuromuscular lesion is a coincidental finding, a mere curiosity or bears any clinical significance.

Reduced-size lung transplantation from adult to neonatal swine.

BACKGROUND: Lung donor shortage is a critical factor limiting the expansion of pediatric lung transplantation programs. This report details the surgical technical feasibility of a training model of lobar lung transplantation as well as the perioperative monitoring to evaluate the appropriate pulmonary graft function. METHODS: Ten hybrid Large-White pigs underwent left lower lobe lung allotransplantation; Donors weighed 15 to 20 kg and recipients 5 to 7 kg. The first five animals were used to learn the surgical anatomy and to establish the surgical technique and instrumentation's model (Group A). One hour after transplantation the right lung was excluded. Lung function and hemodynamic data were collected sequentially in the following five animals (Group B). RESULTS: The left inferior pulmonary lobe was found to be the most suitable allograft for transplantation. Usually, bronchial size discrepancy allowed telescoping of the airway anastomosis. Left atrial clamping was well tolerated during the pulmonary vein anastomoses. Preoperative antiaggregation and postoperatively heparinization achieved with ACT values over 200 seconds, prevented left atrial thrombosis. After right lung exclusion, hemodynamic changes consisted of a sustained increase in pulmonary vascular resistance and a reduction in cardiac output. Lung mechanics were also modified, with a gradual rise in airway resistance and a fall in compliance. CONCLUSIONS: The neonatal pig tolerates left lobar pulmonary transplantation satisfactorily. Although it is a useful and promising surgical learning model, questions remain regarding the applicability of this experience to clinical pediatric lung transplantation.