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Biomedical subjects

H Isaacs

Publications and source records attributed to H Isaacs.

At least 19 recordsLinked to original sources
PubMed1992

Dominantly inherited malignant hyperthermia (MH) in the King-Denborough syndrome.

A 14-year-old boy, an only child, with the phenotypical dysmorphic features of the King-Denborough Syndrome developed a severe hyperthermic episode during anesthesia which responded to the administration of sodium dantrolene. As adequate metabolic studies were not available at the time of the crisis he was referred for confirmation of the malignant hyperthermia (MH) status. Muscle tension studies confirmed the presence of MH. The patient's mother and father were subsequently tested and the mother was found to be MH positive, the father MH negative.

Abnormalities, Multiple↗
PubMed1992

Primary endodermal sinus (yolk sac) tumor of the falciform ligament.

Extragonadal yolk sac tumors (YSTs) are uncommon and YSTs of the liver are exceedingly rare, with only three reported cases in the literature. A case is described of primary YST of the falciform ligament extending into the left lobe of the liver in a 14-month-old boy. This is the first reported case of primary YST arising within the falciform ligament. The patient underwent an exploratory laparotomy after presenting with hemoperitoneum. An extremely friable and necrotic tumor was found extending from the falciform ligament into the liver. The tumor was debulked and the patient received 5 months of chemotherapy employing a modified Einhorn regimen. After a partial response to chemotherapy the patient had a second-look laparotomy, at which time a left hepatic lobectomy and en bloc resection of the falciform ligament was performed in order to remove residual tumor. At the present time the patient has no signs of metastases and is alive and well 2 years after his presentation.

Humans↗
PubMed1992

Benign testicular tumors in children with congenital adrenal hyperplasia.

The association between testicular tumors/nodules and congenital adrenal hyperplasia (CAH) has been previously reported. From 1960 to 1989, three patients (13 to 18 years old) with long-standing CAH developed testicular masses. Two patients with 21-hydroxylase deficiency were diagnosed in the neonatal period while one other with 11-hydroxylase deficiency was diagnosed at 3 years of age when he presented with sexual precocity. In all three patients, medical compliance was poor. The testicular masses were bilateral in two patients and unilateral in one, measured 1 to 2 cm, and occupied only the upper half of the testicle. Testicular biopsy specimens were obtained after at least 6 months of evidence of compliance with the adrenocorticotrophic hormone (ACTH) suppressive medication and failure of the nodules to regress. On gross examination the masses appeared to be firm yellow brown nodules. Light microscopy showed interlacing strands, cords, and rests of cells resembling interstitial (Leydig) cells but with no Reinke crystalloids. Electronmicroscopy in all patients showed variable amounts of both smooth and rough endoplasmic reticulum, the later with occasional dilated cisternae. Follow-up ranged from 6 months to 6 years. No further surgical treatment has been necessary. There has been no evidence of recurrence, distant metastases, or secondary malignancies during the time of follow-up. These findings suggest that testicular tumors may develop from chronic excessive ACTH stimulation of a putative pluripotential testicular cell, a Leydig cell, or an adrenal cortical rest. Unlike other testicular tumors these do not require orchiectomy as the initial form of therapy.

Adolescent↗
PubMed1992

Neuroblastoma masquerading as a retroperitoneal Salmonella abscess.

Symptomatic Salmonella infections usually manifest as self-limited gastrointestinal distress. Patients with chronic systemic illnesses or those who are immunosuppressed may rarely present with Salmonella infection as distant suppurative abscesses. We present a previously healthy Armenian boy who came to medical attention with abdominal pain, fever, and anemia. Abdominal computed tomography (CT) scan showed a cystic suprarenal mass that was surgically explored and found to be a retroperitoneal Salmonella abscess. Postoperative CT scan showed resolving inflammation. A 6-month follow-up CT showed a large suprarenal tumor, which at exploration was found to be neuroblastoma. To our knowledge, Salmonella has never been reported presenting as a solitary retroperitoneal abscess, and neuroblastoma has not been described presenting as a Salmonella abscess. The patient is also unusual because the abscess contained a species unusual for suppurative salmonellosis.

Abscess↗
PubMed1992

Evidence for the localization of a malignant hyperthermia susceptibility locus (MHS2) to human chromosome 17q.

Malignant hyperthermia susceptibility is a lethal autosomal dominant disorder of skeletal muscle metabolism that is triggered by all potent inhalation anesthetic gases. Recent linkage studies suggest a genetic locus for this disorder on 19q13.1. We have previously reported three unrelated families diagnosed with MHS that are unlinked to markers surrounding this locus on 19q13.1. In this report we extend these observations and present linkage studies on 16 MHS families. Four families (25%) were found linked to the region 19q12-q13.2 (Zmax = 2.96 with the ryanodine receptor at theta = 0.0). Five families (31%) were found closely linked to the anonymous marker NME1 (previously designated NM23) on chromosome 17q11.2-q24 (Zmax = 3.26 at theta = 0.0). Two families (13%) were clearly unlinked to either of these chromosomal regions. In five additional families, data were insufficient to determine their linkage status (they were potentially linked to two or more sites). The results of our heterogeneity analyses are consistent with the hypothesis that MHS can be caused in humans by any one of at least three distinct genetic loci. Furthermore, we provide preliminary linkage data suggesting the localization of a gene in human MHS to 17q11.2-q24 (MHS2), with a gene frequency of this putative locus approximately equal to that of the MHS1 locus on 19q.

Adult↗
PubMed1992

Malignant hyperthermia. An historical vignette.

This paper reports previously unpublished accounts of the deaths in 1915 and 1919 of two members of the same family during general anaesthesia. The deaths were subsequently ascribed to a 'hereditary susceptibility' to chloroform. Contemporary evidence is presented which suggests that these deaths were among the very earliest examples of malignant hyperthermia to be described.

Child, Preschool↗
PubMed1992

Hereditary motor and sensory neuropathy type I, associated with aplasia cutis congenita: possible X-linked inheritance.

We report a family with possible X-linked recessive HMSN I with minor signs of the disease and abnormal sensory conduction studies evident in female carriers. There is a previously undescribed association with aplasia cutis congenita in both affected males, and a history of a severe skull defect in a third male child, who died at birth. The latter defect usually shows an autosomal dominant pattern of inheritance.

Adolescent↗
PubMed1992

Internalised capillaries, neuromyopathy and myalgia.

Internalised capillaries are described in the muscle fibres of two adult males who complained of exertional myalgia. In one patient, "bundles" of internalised capillaries were found in 2% of the Type 1 fibres and many of the Type 1 fibres exhibited non-specific cytoarchitectural changes. The other had hereditary motor and sensory neuropathy (HMSN) Type 2 and his muscle biopsy exhibited the more conventional single and double internalised capillaries in 3% of the muscle fibres in addition to the anticipated neuropathic changes. Electron microscopy revealed the presence of paracrystalline inclusions in the mitochondria of muscle of both patients. Dystrophin was normal on both immunogold/silver staining and immunoblotting. Sixty five of 77 recorded patients with evidence of internalisation of capillaries have been males and 10 are known to have complained of muscle cramps or severe myalgia. An ischaemic pathogenetic predisposition is proposed as a possible stimulus to the capillary internalisation, formation of paracrystalline mitochondrial inclusions and myalgia.

Adult↗
PubMed1991

Centronuclear myopathy--an inherited neuromuscular disorder. A report of 3 cases.

Three patients with the adult form of centronuclear myopathy are presented. The slow progression of this disorder is confirmed. The investigations included muscle and sural nerve biopsies. The electron microscopic findings in the muscle of these patients are unique, as are the results of histological examination and histochemical tests. The sural nerve studies were within normal limits. Insulin estimations in response to glucose loading were normal, which largely negates the possibility of an insulin-receptor defect in this disorder.

Adult↗
PubMed1991

Kinase activity and protein phosphorylation in control and malignant hyperthermic skeletal muscle.

1. Native 6% Laemmli gels were used to resolve 7 protein kinase activity bands in control and malignant hyperthermia (MH)-susceptible porcine and human skeletal muscle extracts. 2. MH-susceptible samples were consistently more active than the controls. 3. Following halothane treatment, a 43 kDa component displayed increased phosphorylation by a calcium-calmodulin dependent kinase in MH-susceptible vs control human samples. 4. Increased phosphorylation of additional endogenous protein components of molecular mass 116 and 60 kDa was observed.

Animals↗
PubMed1991

Pulmonary blastoma: a rare childhood malignancy.

Pulmonary blastoma is a rare primary malignancy of the lung, with few cases reported in children. The tumor consists of mesenchymal and epithelial components resembling the fetal lung. Seven children (aged 18 months to 5 years) with pulmonary blastoma were studied. The pulmonary radiographic patterns seen were a large, space-occupying solid mass with opacification of the hemithorax and preexisting cystic disease with a small solid tumor component. Computed tomographic images showed a low-attenuation mass with whorls of high-attenuation solid tissue. Four of the seven patients died within 2 years despite surgery and therapy; of the three surviving patients, one has recurrent disease.

Child, Preschool↗
PubMed1991

Results of treatment of malignant germ cell tumors in 93 children: a report from the Childrens Cancer Study Group.

We report treatment results in 93 children entered on study from 1978 to 1984 with malignant germ cell tumors (MGCTs), excluding dysgerminoma and tumors of the testis or brain. The estimated 4-year survival and event-free survival (EFS) for all 93 patients were 54% and 49%, respectively. For 30 children with ovarian tumors, the estimated 4-year survival was 67% and EFS was 63%. For 63 children with nongonadal tumors, survival and EFS were 48% and 42%, respectively. The comparison of EFS between ovarian and nongonadal tumors was significant at P = .03. The treatment plan included a second-look surgical procedure after 18 weeks of chemotherapy. Over half of 36 patients evaluated as having a residual mass present immediately before second-look surgery had no malignant tumor after review of surgical specimens. Age greater than 11 years at diagnosis, incomplete removal of tumor at first surgery, and more than one structure or organ involved at diagnosis increased the risk for adverse event. The histologic subtype of the primary tumor was not related to outcome. Diagnosis was verified by independent pathologic review, and treatment was uniform. Seventeen percent of all registered patients (21 of 127) were excluded because of ineligible pathologic diagnoses; sixty percent (13 of 21) were immature teratomas.

Adolescent↗
PubMed1990

An association between certain congenital abnormalities and the malignant hyperthermia trait.

Although an association between malignant hyperthermia (MH) and congenital abnormalities has been recorded, no prospective study has been attempted to investigate this relationship. Standardised in vitro muscle tests were performed, because of impending anaesthesia for corrective surgery, on 25 children with birth defects similar to those induced by hyperthermia in laboratory animals, and in whom excessive pyrexial reactivity to anaesthesia, drugs or stress were recorded. Fifteen of the 25 children were MH positive by responding abnormally to the administration of halothane/caffeine. Five of these patients reacted positively to both caffeine and halothane, while the remainder manifested a contractile response to halothane only. This study underlines the existence of an anaesthetic risk factor associated with certain congenital abnormalities and neurodevelopmental delay and emphasises the need for further research to elucidate the possible importance of heat stress during fetal development in genetically susceptible individuals.

Adolescent↗
PubMed1990

Mesenchymal hamartoma of the liver. A 35-year review.

Mesenchymal hamartoma of the liver occurs almost exclusively in infancy and childhood, with approximately 140 total cases reported. We report the experience with 18 patients at the Childrens Hospital of Los Angeles (Calif) during the past 35 years. The charts of all patients with mesenchymal hamartoma were retrospectively reviewed. The mean age at presentation was 16 months. Thirteen patients were symptomatic, presenting with increasing abdominal distention. Physical examination revealed an abdominal mass or hepatomegaly. Ultrasonography and computed tomography were the most useful diagnostic tests. Fourteen patients underwent resection; 9 underwent hepatic resection and 5 underwent excision of the tumor only. One patient had marsupialization, 1 underwent a biopsy only, and 2 died of unrelated causes and the hamartoma was found incidentally at autopsy. In all instances, a large cystic mass with well-demarcated margins was found. Three patients were unavailable for follow-up and 13 patients were alive and well 1 month to 24 years (mean, 5 years) after diagnosis. Recurrence or malignant transformation was not noted. A presumptive diagnosis can be made preoperatively by normal laboratory values and a combination of ultrasonography and computed tomography. We recommend excision of the tumor in all patients once the diagnosis is made, with the expectation of complete recovery.

California↗
PubMed1990

Role of chemotherapy in pediatric pulmonary blastoma.

Pulmonary blastoma is a rare malignant tumor of the lung that has been treated primarily with surgery. The effect of combination chemotherapy has not been systematically investigated. Two pediatric cases are reported in whom combination chemotherapy consisting of vincristine, actinomycin-D, cyclophosphamide, cis-platinum, and adriamycin was successfully used. The first case, a 5-year-old boy, underwent incomplete surgical excision of the tumor followed by a 104-week course of combination chemotherapy. The second case is a 3-year-old boy who was initially treated with combination chemotherapy that resulted in an objective response; he subsequently underwent surgical excision. This intensive combination chemotherapy is effective both in inoperable tumors as initial therapy as well as a surgical adjuvant.

Antineoplastic Combined Chemotherapy Protocols↗