Pheochromocytoma and pregnancy: a case report and review of anesthetic management

PURPOSE: To describe a patient diagnosed with pheochromocytoma in the third trimester of pregnancy and discuss the perioperative and anesthetic management. CLINICAL FEATURES: A 32-yr-old previously healthy woman (gravida 4, para 2) presented to our tertiary care obstetrical hospital at 34 weeks five days gestation with a history of labile blood pressure and severe hypertension. A week prior to admission she began having episodes of severe headache, dizziness, sweating and nausea. On a routine obstetric visit she was noted to be severely hypertensive with a blood pressure of 200/120 mmHg. Biochemical investigations confirmed the diagnosis of pheochromocytoma and magnetic resonance imaging demonstrated a 3 cm x 3 cm right adrenal mass. The patient was invasively monitored in the intensive care unit and treated with alpha- followed by beta-blockade with phenoxybenzamine and metoprolol. A multidisciplinary conference was organized involving endocrinology, anesthesiology, general surgery and obstetrics to determine the most appropriate management of the patient. An uncomplicated laparoscopic adrenalectomy was performed following a period of recovery after an uneventful elective Cesarean delivery. CONCLUSIONS: The primary goals in the management of pheochromocytoma in pregnancy are early diagnosis, avoidance of a hypertensive crisis during delivery and definitive surgical treatment. Timing of surgical resection will depend on the gestational age at which diagnosis is made. Cesarean section is the preferred mode of delivery when the tumour is still present. This case illustrates that with antenatal diagnosis, advanced methods of tumour localization, adequate preoperative adrenergic blockade and team planning, pheochromocytoma in pregnancy can be treated successfully.     

9p21 and 13q14 dosages in ependymomas. A clinicopathologic study of 101 cases.

Ependymomas are glial neoplasms whose clinical behavior is difficult to predict based on histology alone. Recently, a comparative genomic hybridization study identified frequent chromosome 9p and 13q losses in anaplastic ependymomas, suggesting that p16 and RB alterations may be involved in tumor progression. In order to test this hypothesis further, 101 myxopapillary, conventional, and anaplastic ependymomas (51 spinal and 50 intracranial tumors) were tested for RB and p16 deletions using fluorescence in situ hybridization. Clinical follow-up, ranging from 2 to 198 months (median 46 months), was obtained in 90 cases (91%). RB and p16 deletions were seen in 22 of 92 (24%) and 22 of 89 (25%) informative cases, respectively. Polysomies were more frequent in the grade I and II spinal tumors, consistent with prior reports of increased aneuploidy in such cases. No significant genetic associations were seen with tumor grade, recurrence, or death, suggesting that 9p and 13q deletions do not play a prominent role in the malignant progression of ependymomas, as has been implicated in other glioma subtypes.     

Non-familial juvenile polyposis with histological evidence of adenomatous transformation.

A 14-year-old male presented with abdominal pain, diarrhoea and a sensation of something prolapsing through the anus during defecation, and was found to have diffuse colonic polyposis. There was no evidence of mucocutaneous hyperpigmentation and family history was negative, suggesting a diagnosis of non-familial juvenile polyposis. Histological analysis of multiple endoscopic biopsies showed features typical of juvenile or retention type (hamartomatous) lesions: dilated cystic glands lined by mucocus-secreting epithelium and prominent, inflamed and congested lamina propria. However, admixed with these features, focal areas of atypical adenomatous changes were recognized. Even the intervening normal-looking colonic mucosa showed some dysplastic changes. These findings indicate that hamartomatous and atypical adenomatous epithelial changes can co exist in non-familial juvenile polyposis and the latter may confer a risk of malignant transformation in this otherwise non-neoplastic disease.     

True epiphrenic diverticulum of esophagus secondary to tubercular adenitis.

Ephiphrenic esophageal diverticulum is rare and usually is a pulsion-type pseudodiverticulum that occurs in association with motility disorders of the esophagus. We report a 35-year-old man with tubercular lymphadenitis causing true traction type of epiphrenic diverticulum. Esophageal diverticulectomy and esophagomyotomy was done; he is doing well on antitubercular drugs.     

External duodenal fistula following closure of duodenal perforation.

AIM: Retrospective analysis of experience with management of external duodenal fistula (EDF) without using total parenteral nutrition (TPN). METHOD: Medical records of 31 patients with EDF following closure of duodenal ulcer perforation, treated over a 7-year period (1994-2001), were studied. Twenty-one patients (68%) had evidence of sepsis at presentation or during the course of treatment. None could afford TPN for optimum time. All patients received hospital-based enteral nutrition through nasojejunal tube, besides supportive medical treatment and/or surgery. Peritonitis or failure to insert nasojejunal tube for enteric alimentation led to early surgery. RESULTS: Two patients died of septicemia and multi-organ failure within 48 hours of admission. Fourteen patients (48.3%) initially received conservative treatment (Group I); six of them later required surgery. Fifteen patients (51.7%) underwent early surgery due to peritonitis (n=9) or failure to establish enteral feeding (n=6) (Group II); wound infection, intra-abdominal abscess and septicemia were more common in these patients than those in Group I. Survival rate was higher in Group I than in Group II (86% versus 40%; p< 0.05). Septicemia and gastrectomy were the independent factors associated with high mortality. CONCLUSIONS: EDF can be satisfactorily managed without TPN. Successful placement of enteral feeding line, supportive treatment and delayed surgery can achieve survival in 85% of patients. Minimum intervention is recommended when early surgery is performed in peritonitis or to establish enteral feeding line.     

Scleromyxoedema with features of systemic sclerosis.

The case is described of a patient with scleromyxoedema with features typical of systemic sclerosis. The features were so characteristic that the disease was misdiagnosed as systemic sclerosis. A brief review of the association of the two diseases is given.     

Modification of apomorphine-induced behaviour following chronic swim exercise in rats.

Four week swim exercise schedule (45 min day-1, 6 days each week) in rats led to a significant adaptive change in functional responsiveness of dopamine receptors (auto-receptors) in the nigrostriatal and mesolimbic system that was evident from the modification of behavioural responses elicited by a low dose of apomorphine, a direct acting dopamine receptor agonist. Thus, a remarkable increase in yawning response, development of full blown stereotypy, as well as profound attenuation of locomotory and hypothermic response was observed in exercise-trained rats as compared with the non-exercise group (control), following intraperitoneal administration of 0.3 mg kg-1 of apomorphine.     

Antagonists that demonstrate species differences in neurokinin-1 receptors.

125I-Bolton-Hunter-substance P (125I-BH-SP) binding properties of three novel classes of neurokinin-1 (NK-1) receptor antagonists were investigated in tissues derived from humans, guinea pigs, and rats. 125I-BH-SP was shown to bind to a single class of binding sites, with similar dissociation constants, Kd, in human astrocytoma cells (U-373 MG), human urinary bladder, guinea pig forebrain, guinea pig ileum longitudinal smooth muscle, rat forebrain, and rat duodenum. In each tissue preparation, known peptide agonists and peptide antagonists yielded potencies typical for a NK-1 receptor profile, with little difference in binding properties between the various tissues. However, when the three classes of compounds, heterosteroids, cyanines, and modified peptides, were tested for their ability to displace 125I-BH-SP binding from the NK-1 receptor, very different binding profiles were observed. The heterosteroids were shown to be as much as 3 orders of magnitude more potent in tissues derived from rats than from humans or guinea pigs. A distinct species-dependent structure-activity relationship (SAR) was also observed for this class of compounds. Like the heterosteroids, the cyanines displaced 125I-BH-SP with 10-30-fold higher affinity in rat tissues than in human and guinea pig tissues. However, the SAR generated by the cyanines was comparable in all tissues studied. The modified peptides, on the other hand, were up to 10-100-fold more potent in human and guinea pig than rat tissues, producing a SAR that differed between the various species. No differences in binding properties between central nervous system and peripheral tissues from the same species were seen with these compounds. These results provide evidence for species differences in NK-1 receptors in humans, guinea pigs, and rats. Because it is known that there exists great sequence identity between rat and human NK-1 receptors, it is hypothesized that key amino acid changes or different lipid environments within the transmembrane binding region of the receptor may account for the observed species difference. Furthermore, this study emphasizes that caution is necessary in the choice of species to be used in development programs targeted towards therapeutic entities in the NK-1 receptor antagonist area.