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Biomedical subjects

M Di Lorenzo

Publications and source records attributed to M Di Lorenzo.

At least 19 recordsLinked to original sources
PubMed1996

Chromosomal anomalies in newborns with omphalocele.

Omphalocele is the most common congenital abdominal wall defect; its reported incidence is 1 in 4,000 to 5,000 live births. With large defects, the liver is a median organ and lies within the sac (extracorporeal liver [ECL]). With small defects, only bowel or stomach is found outside the abdominal cavity (intracorporeal liver [ICL]). The goal of this study was to determine whether a relationship exists between the sac contents or the timing of diagnosis and the incidence of chromosomal abnormalities or survival among fetuses and newborns with omphalocele. From 1985 to 1995, 83 cases of omphalocele were managed at the authors' institution. In 50 cases the diagnosis was made using prenatal ultrasonography. All patients underwent fetal cardiac echography and amniocentesis. Twenty-four pregnancies were terminated electively because of severe associated anomalies. Of the 59 live births, 41 patients (69%) survived. The incidences of cardiac, chromosomal, and other anomalies were 24% (14), 10% (6), and 21% (16), respectively. Omphalocele with ICL is associated with a better survival rate than omphalocele with ECL (82% v 48%; P < .01) despite the significantly higher rate of karyotype abnormalities (16% v 0%; P < .05). The prognosis was poorer for patients with prenatally diagnosed omphalocele than for those with a postnatal diagnosis (mortality rate, 42% v 21%) because the former group had a higher percentage (70% v 9%) of ECL. Although the incidence of cardiac anomalies was similar for the ECL and ICL groups (33% v 18%), the former had more complex malformations. Death usually occurred in newborns who had neonatal respiratory distress owing to prematurity, or in those with chromosomal or cardiac anomalies. Chromosomal anomalies occurred mainly in cases of small omphaloceles that contained gut only, and it was the major cause of death among this group. In ECL cases, survival was primarily affected by the associated complex cardiac anomalies.

Chromosome Aberrations↗
PubMed1995

An intraluminal model of necrotizing enterocolitis in the developing neonatal piglet.

UNLABELLED: The most common risk factors for the development of necrotizing enterocolitis (NEC) are prematurity and enteral feeding. Most models of NEC involve ischemic insult resulting in generalized necrosis, different from the classical ileocecal predilection of NEC. This anatomic predisposition is explained by dysmotility of immature gut, leading to bacterial overgrowth in the terminal ileum and colon. Infant formula containing lactose as the sole carbohydrate source overwhelms partially developed lactase activity, allowing enteric bacteria to ferment excess carbohydrate to short-chain fatty acids, decreasing intraluminal gut pH and predisposing to mucosal injury. Impaired clearance of intraluminal contents exacerbates this effect. In the present study the authors used a model of NEC, originally developed in rabbits and based on analysis of intestinal contents of NEC babies, modified and adapted here to neonatal piglets, the gastrointestinal tract of which more closely resembles the human neonate. METHOD: Piglets < 3 days old and 2 weeks old were laparotomized. Loops created from the distal ileum to the proximal colon were injected with isoosmolar acidified casein solution or 0.9% saline. Segments were harvested 3 hours later, sectioned for H&E, and graded from 0 (intact villi) to 4 (transmural necrosis). RESULTS: Acidified casein-induced damage included areas of necrosis, submucosal edema, inflammatory cell infiltrate, and lymphatic distension. In younger animals, lesions were more pronounced (3.25 +/- 0.13 for the < 3-day-old v 2.43 +/- 0.14 for the 2-week-old piglets; P < .005). CONCLUSION: The authors believe that this piglet NEC model most closely approximates human NEC because it incorporates two of the most common risk factors: dysmotility (by creating intestinal loops) and enteral feeding (by intraluminal injection of acidified casein).

Aging↗
PubMed1995

Use of L-arginine in the treatment of experimental necrotizing enterocolitis.

UNLABELLED: Although multifactorial in etiology, prematurity and feeding are two of the most common risk factors associated with necrotizing enterocolitis (NEC). To understand the pathogenesis of NEC, the complex interaction between intestinal contents and clearing mechanisms in the immature human gut must be elucidated. Nitric oxide (NO) is a proposed mediator of nonadrenergic noncholinergic neural inhibition, causing relaxation in the gut. In addition to its role as a neuroeffector substance, studies suggest that endogenous formation of NO maintains intestinal mucosal integrity, protecting the gut from blood-borne toxins and tissue-destructive mediators. Thus, NO has a dual role in both gut smooth muscle relaxation and mucosal protection. Because two of the primary risk factors in the development of NEC are prematurity (as it relates to gut dysmotility) and enteral feeding (as it relates to mucosal damage by intraluminal substrate), the authors chose to investigate the role of NO in the pathogenesis of NEC induced by intraluminal injection of acidified casein solution in neonatal piglets. METHODS: Having confirmed the consistent induction of NEC both macroscopically and histologically with this model (n = 32), the following were undertaken. Neonatal piglets (< 3 days old) were laparotomized, and intestinal loops were created from the terminal ileum to the proximal colon. The loops were injected with acidified casein solution and separated by saline-injected control loops. When the abdomen was closed, a continuous peripheral intravenous infusion of L-arginine, an NO synthase substrate (600 mg/kg/h [n = 6]), or N-omega-nitro-L-arginine methyl ester (L-NAME), an NO synthase inhibitor (20 mg/kg/h [n = 6]), was begun. Gut segments were harvested 3 hours later and processed for evaluation of the extent of necrosis. RESULTS: Macroscopically, the L-NAME-treated group showed areas of hemorrhagic necrosis in the NEC-induced loops. The L-arginine-treated group had greatly diminished or virtually absent lesions. H&E-stained sections were graded microscopically, using a scale from 0 to 4, ranging from intact villi (grade 0) to transmural necrosis (grade 4). In the untreated NEC group, intestinal damage in the acidified casein loops was exhibited by areas of necrosis (extending, in some cases, transmurally), submucosal edema, and inflammatory cell infiltrate (average grade, 3.5). In the L-NAME-treated group, the intestinal damage was similar to that of the NEC-induced group (average grade, 3.5), but also presented with marked hemorrhagic congestion. In the L-arginine group, NEC-induced tissue damage was greatly attenuated, with necrosis limited primarily to the villus tips (average grade, 1). Nevertheless, inflammatory cell infiltrate and mild submucosal edema were still present. CONCLUSION: Continuous intravenous infusion with the NO synthase substrate L-arginine markedly attenuates intestinal injury in this neonatal piglet model of NEC. Intravenous administration of the NO synthase inhibitor L-NAME causes hemorrhagic congestion of the gut wall. Based on these findings, the authors propose that treatment with the amino acid L-arginine should be considered as a potential therapeutic modality for NEC.

Amino Acid Oxidoreductases↗
PubMed1993

Childhood primary pulmonary neoplasms.

Nine children (6 boys, 3 girls) were diagnosed with a primary endobronchial or pulmonary parenchymal neoplasm. The average age at diagnosis was 9 years. Presenting complaints included cough (7), fever (5), pulmonary infection (3), respiratory distress (3), weight loss (2), pain (2), and hemoptysis (1). Pulmonary x-rays showed persistent atelectasis, pneumonic infiltrates or mass lesions. A computed tomography scan was performed in 8. Five of six endobronchial tumors were diagnosed with bronchoscopy and biopsy. Treatment consisted of thoracotomy and pulmonary resection in 7 cases and laser resection in 2. The pathologic diagnoses were bronchial carcinoid (3), bronchial mucoepidermoid carcinoma (1), inflammatory pseudotumor (plasma cell granuloma) of the bronchus (2) and of the lung parenchyma (1), fibrosarcoma (1), and rhabdomyosarcoma (1). Postoperative chemotherapy was given only to the patient with pulmonary rhabdomyosarcoma; this child died. One child has developed a local recurrence while 7 children are alive and free of disease at an average of 2.4 years postresection. Pulmonary neoplasms are unusual in the pediatric age group and represent a wide spectrum of pathology. Including the present series, 383 tumors have been described. Seventy-six percent were malignant. Early investigation and surgical intervention are essential in children with persistent pulmonary symptoms or x-ray abnormalities. In most cases, the prognosis is excellent with complete surgical resection; however, malignancies other than bronchial adenoma are associated with significantly mortality.

Bronchial Neoplasms↗
PubMed1993

Blunt abdominal trauma in children: the practical value of ultrasonography.

The occult nature of blunt abdominal trauma justifies the need for reliable diagnostic adjuncts to physical examination. From June 1988 to June 1991, 259 children admitted to the general surgery/trauma service underwent abdominal ultrasonographic scanning (US). A total of 116 abdominal lesions were found in 81 patients. Ultrasonography alone had a sensitivity of 89%, a specificity of 96%, and an overall accuracy of 94%, as determined against the overall diagnostic workup and clinical course (mean follow-up, 17.4 weeks). In 44% of the patients, US was used alone; in 49% one or two additional tests were performed, and in only 7% were three or more tests required. Compared with computed tomography, US is more versatile, easier to perform in children, and more cost effective, even with the addition of a functional imaging modality. Although not demonstrated by this preliminary, retrospective study, Doppler US appears to be the logical complement to abdominal ultrasonography in the evaluation of children with blunt abdominal trauma.

Abdominal Injuries↗
PubMed1993

[Heparin and lipoprotein(a). Observations during hemodialysis].

The effect of heparin (bolus e.v. 5.000 I.U.) on blood levels of Lp(a) and other lipids (triglycerides, -HDL, -LDL and total cholesterol, apo A1, apo B100 and apo A1/apo B100) was studied in 15 patients (8 M and 7 F) with chronic renal failure during hemodialysis. Statistically significant reductions of the basal values were found for Lp(a) and the other lipids in the blood taken before the beginning of dialysis, 30 min' after the heparin bolus. The analysis of third blood sample (at the end of the hemodialysis, one hour after the end of the heparin maintenance infusion) showed a rise of HDL and LDL-lipoproteins over the basal values clearly in relation to reduced heparin and plasmatic fraction of the blood. The values of Lp(a) had not so high increase as consequence of more elevated affinity with heparin and of a possible enhanced metabolic rate via lipoprotein lipase. The authors, in agreement with similar changes of Lp(a) and other lipids previously observed in patients with coronary diseases during bypass surgery in extracorporeal circulation or angioplasty, (interventions requiring generous heparin treatment), believe to have now sufficient data for attributing heparin a causal role for the above mentioned effects. The authors stress the needing of other studies better understand the action to mechanisms of heparin and to evaluate possible future clinical applications of this new interesting Lp(a)-clearing effect.

Aged↗
PubMed1992

Complications of lymphangiomas in children.

One hundred ninety-three cases of lymphangioma presenting in children were reviewed over a 10-year period. The diagnosis was established before 5 years of age in 87.0%. The distribution of lymphangiomas was: cervical (31.4%), craniofacial (18.9%), extremity (18.9%), trunk (9.2%), intraabdominal (9.2%), cervicoaxillothoracic (4.9%), multiple (3.8%), cervicomediastinal (2.2%), and intrathoracic (1.6%). Of 164 patients undergoing primary therapy, total excision was performed in 77.4% and partial excision in 20.7% with recurrence rates of 11.8% and 52.9%, respectively. Thirty-eight percent of all operations for lymphangiomas were performed for resection of recurrent or residual disease. The incidence of postoperative complications was 31.3%. Forty-four additional procedures were required to manage these complications. Sclerotherapy with 50% dextrose was used as an adjunct in 9.5%. Recurrences were seen after total resection in 17.6% of operations in which 50% dextrose was used and 11.8% in which it was not used. Seroma formation was noted in 3.5% of total resections and 40.0% of resections for recurrent disease in which adjunctive sclerotherapy with 50% dextrose was used. Seromas occurred in 9.8% of wounds in which local drains were used and 3.6% of wounds in which drains were not used. Infectious complications occurred after 6.6% of operations using perioperative antibiotics and 3.5% not using antibiotics. The management of lymphangiomas in children remains a difficult problem. Despite being benign lesions, lymphangiomas are attended by a high rate of morbidity from complications of the disease and its management. Complete excision still offers the best chance for complete cure. Sclerotherapy with 50% dextrose is not beneficial in the management of recurrent disease or postoperative seromas. Local drains and perioperative antibiotics do not appear to diminish the incidence of seromas and infectious complications, respectively.

Child, Preschool↗
PubMed1991

Sirenomelia in an identical twin: a case report.

Sirenomelia, or the mermaid syndrome, is the most extreme example of the caudal regression syndrome. It invariably presents with lower limb fusion, sacral and pelvic bony anomalies, absent external genitalia, anal imperforation, and renal agenesis or dysgenesis. Because of the resultant oligohydramnios, these infants most often have Potter's facies and pulmonary hypoplasia. There are approximately 300 cases reported in the literature, 15% of which are associated with twinning, most often monozygotic. The syndrome of caudal regression is thought to be the result of injury to the caudal mesoderm early in gestation. It has been suggested that the association of the most extreme form of caudal regression, sirenomelia, with monozygotic twinning may represent developmental arrest of the primitive streak, with creation of a second primitive streak that gives rise to the usually normal twin. The embryology of the various presentations of the caudal regression syndrome may be further delineated by studying infants with this dramatic and fatal syndrome.

Diseases in Twins↗
PubMed1990

Malignant thymoma in children: a 20-year review.

Malignant thymomas are extremely rare in children, with only 27 cases reported thus far in the pediatric surgical literature. We report four additional cases diagnosed at this institution over the past 20 years (ages 3 to 14 years). Clinical presentations included superior vena cava syndrome, cough, dyspnea, cyanosis, enlarging mediastinal mass, spontaneous pneumothorax, and pleuropericardial effusion. Three patients underwent incomplete resection of the mass or biopsy because of "unresectability" and were treated with radiotherapy and adjunctive chemotherapy. One patient underwent near complete macroscopic resection as well as radiotherapy and chemotherapy. All patients died at intervals ranging from 6 months to 2 1/2 years after diagnosis. Three patients were found to have metastatic disease prior to death or at autopsy. In one case, the initial pathological diagnosis was lymphocytic thymoma. After ultrastructural studies were performed, the diagnosis was changed to thymic T-cell lymphoma. This patient subsequently developed acute lymphoblastic leukemia 3 months after surgical resection followed by radiotherapy. Malignant thymomas are highly aggressive tumors in children. A radical surgical approach with complete excision of the tumor and contiguous structures in continuity, with adjunctive radiotherapy and chemotherapy remains the only hope for survival in children with these rare lesions.

Adolescent↗
PubMed1990

Multiple small bowel perforations in leukemia secondary to Epstein-Barr virus lymphoma with survival: a case report.

This is the case report of a 4-year-old white boy who was diagnosed as having acute lymphoblastic leukemia (ALL) in November 1985. While in remission and on maintenance chemotherapy, he developed a primary Epstein-Barr virus (EBV) respiratory infection in October 1986. On October 27, 1986 a plain abdominal radiograph taken for abdominal distention showed free air. At celiotomy, multiple nodules were noted to stud the small bowel. Central necrosis of these nodules with perforations were present in the distal small bowel. Resections and end-to-end anastomoses were performed. Three days later the patient again had a similar acute abdominal episode. At reexploration, similar lesions in the liver, kidney, duodenum, proximal jejunum, and colon were found. Liver biopsy as well as intestinal resections and end-to-end anastomoses were performed, along with a loop ileostomy. Polymorphic B-cell lymphoma positive for EBV was found in the specimens. After cessation of chemotherapy and institution of abdominal radiotherapy, the hepatic and renal lesions were seen to resolve on computed tomography scan. The patient's course was complicated by the development of cervical and mediastinal abscesses that were drained, and E coli sepsis accompanied by chronic diarrhea requiring intravenous hyperalimentation. By January 1988, he appeared to be recovering. His ileostomy was closed in March 1988. Despite cessation of chemotherapy since October 1986, the patient is now well and in complete remission.

Child, Preschool↗
PubMed1989

Bronchogenic cysts.

Between 1967 and 1987, 26 patients with bronchogenic cysts were treated in our institution: 15 females and 11 males, ranging in age from 2 months to 14 years (average 6 years, 4 months). Only four patients (15%) were 1 year old or less. Seven patients presented with asymptomatic lesions discovered on chest film. Nineteen patients presented with respiratory symptoms. Of note are the four patients aged 1 year or less, who presented with dyspnea and cyanotic spells. Only one of them presented with dysphagia. All patients underwent routine chest films and tomography and, later, computed tomography (CT) scan of the thorax once the study became available. Barium esophagogram and bronchoscopy were performed as required. Contrary to what has been published concerning the intraparenchymal location of bronchogenic cysts, the majority of the cysts (65%) were located in the mediastinum, usually in close proximity to the carina, mainstem bronchi, trachea, esophagus, or pericardium. Only 27% (7 of 26) were intraparenchymal, and 8% (2 of 26) were situated in the inferior pulmonary ligament. A correct preoperative diagnosis was made in 19 patients (73%). Intrapulmonary lesions were removed by segmentectomy or lobectomy. Cysts located elsewhere were simply excised. Among the cysts adhering to the trachea, 50% (two of four) required suture of the membranous trachea after excision. Postoperative complications included one pneumonia, which responded to antibiotics, and one transient paresis of the right phrenic nerve. Follow-up averaged 17 months (range, 0 to 17 years). No sequelae were noted and all patients were cured.

Adolescent↗
PubMed1989

Malignant small-cell tumor of the thoracopulmonary region: 'Askin tumor'.

Malignant small-cell tumor of the thoracopulmonary region (MSCT) is an uncommon neoplasm in children. We describe five cases diagnosed since 1981 that fulfill the criteria put forth by Askin et al. Surgery was performed for diagnosis or therapy in all patients. Two patients underwent open lung biopsy, only because of tumor extent. The other three had chest wall resections. All patients received radiotherapy and chemotherapy. Three patients presenting initially with extensive disease died at intervals of 2.5 to 7 months after diagnosis. Two patients are alive and disease-free at 16 and 24 months postdiagnosis. All five cases were reviewed for standard histology and differential immunohistochemistry. Electronmicroscopy and tissue cultures were done in 3 of the 5 patients. All five patients were neuron-specific enolase-positive. MSCT is an exclusion diagnosis not always readily made. Clinical course and pathologic expertise may point to the correct diagnosis.

Adolescent↗
PubMed1988

A twenty-year experience with thyroid carcinoma in children.

During the past 20 years, 23 patients (7 males, 16 females) were operated on for thyroid carcinoma in our institution. The average age was 13.6 years (range, 22 months to 27 years). Our series includes papillary carcinoma in 11, follicular carcinoma in four, and medullary thyroid carcinoma in eight patients. Follow-up ranged from 8 months to 20.3 years, with an average of 7.5 years for well-differentiated carcinomas and 4.3 years for medullary thyroid carcinomas. All patients are presently alive with no evidence of progressive disease. Patients with papillary and follicular carcinomas underwent partial thyroidectomy; those with medullary carcinoma underwent total thyroidectomy. Serious complications included three permanent hypoparathyroidism and two tracheostomies, all after secondary neck explorations. The overall results observed in our series of patients seem to support the current conservative approach to well-differentiated thyroid carcinoma, reserving total thyroidectomy for medullary cancer of the thyroid. A more aggressive search for familial medullary carcinoma through use of pentagastrin stimulation leads to early detection and more effective therapy.

Adenocarcinoma↗
PubMed1988

Blunt pancreatic injuries in children: the role of percutaneous external drainage in the treatment of pancreatic pseudocysts.

During the past 10 years, 26 cases of blunt pancreatic trauma were diagnosed in our institution. In 42.3% (11/26) the accident was bicycle-related. Seventy-three percent of patients were seen within 48 hours of injury. The most frequent clinical presentations included abdominal pain, tenderness and vomiting. Diagnosis of pancreatic injury was suggested by hypermylasemia in most cases. Associated trauma was seen in seven patients (26.9%) and it was intraabdominal in four (15.3%). Computerized tomography (CT) scan is the single most useful radiologic investigation in evaluating pancreatic trauma. Ultrasound, although less accurate than CT scan in determining the severity of the initial injury, is useful in the evaluation and treatment of pancreatic pseudocysts. Pancreatic pseudocysts developed in ten patients. Spontaneous resolution occurred in five (50%). In three patients, percutaneous external drainage (PED) was successful in treating pancreatic pseudocysts without complications or recurrence at 11, 19, and 31 months. PED is a suitable form of treatment in selected cases of pancreatic pseudocysts. Results in children are better than in the adult population, probably due to the absence of primary pancreatic pathology. We believe that PED should be considered the primary therapeutic procedure for traumatic pancreatic collections prior to more invasive surgical treatment, when there is no evidence of pancreatic duct transection on CT scan.

Adolescent↗
PubMed1988

Pulmonary metastases in children: results of surgical treatment.

A retrospective analysis, from 1965 to 1987, of 22 patients less than 18 years of age undergoing thoracotomy for pulmonary metastases from previously diagnosed malignancy, was performed. There were 15 males and seven females whose ages ranged from 8 months to 17, years. Ten patients had primary osteogenic sarcoma, five had Wilms' tumor, and seven had miscellaneous other tumors. A total of 41 thoracotomies were performed with no mortality. The overall survival rate was 54.5%, with an average survival of 6.2 years after initial diagnosis. The osteosarcoma group had a 50% survival rate after an average of 62 months from initial diagnosis, while the Wilms' tumor group had an 80% survival rate with a 100-month average. The remaining seven patients had a 29% average survival rate 62 months after diagnosis. Of the 12 patients undergoing wedge resections, two died upon follow-up 20 and 21 months after initial diagnosis. As opposed to the survivors in this group, both required more than four wedge resections upon initial thoracotomy. Two patients requiring extended resections, one for Ewing's sarcoma and one for hepatoblastoma, died 35 and 3 months after diagnosis, respectively. Of the eight patients undergoing lobectomy and/or segmentectomy, 75% died an average of 31.3 months after diagnosis. Ten patients had two or more thoracotomies for an average of 2.9, with a 40% survival rate. Of the 27% who presented with initial bilateral lung metastases, 33% survived. Forty-five percent of patients had a tumor-free interval of less than 12 months prior to thoracotomy, resulting in a 60% mortality rate.(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗