The management of a neck mass: presenting feature of an asymptomatic head and neck primary malignancy?

Malignancy of the upper aerodigestive tract is not always associated with obvious localizing symptoms. Presentation may then only be prompted by the appearance of a hard mass in the neck, a metastasis to a cervical lymph node. Neck exploration without a prior diligent search for an occult head and neck primary tumour is to be avoided as it compromises subsequent treatment. The diagnostic investigation of 112 patients complaining solely of a painless and enlarging neck swelling is reviewed. An otolaryngologic examination identified an asymptomatic malignancy of the head and neck in 72 patients (64%). Excision biopsy of the neck mass was required to achieve a diagnosis in only 29 (29%) of those patients who had not already undergone surgery. These results are presented to emphasize the need for a specialist examination of the head and neck prior to embarking on excision of any suspicious neck mass.     

Epiploic appendagitis and omental infarction: pitfalls and look-alikes

Epiploic appendagitis and omental infarction are benign self-limiting conditions that are more frequent than generally assumed. Both disorders frequently mimic symptoms of an abdominal surgical emergency, often leading to clinical misdiagnosis of appendicitis or diverticulitis. Because a misdiagnosis can result in an unnecessary laparotomy, a correct diagnosis is of great importance. Ultrasound and computed tomography can be used to make a reliable diagnosis. This pictorial essay illustrates the various ultrasonographic and computed tomographic appearances of epiploic appendagitis and omental infarction and focuses on their radiologic differential diagnoses and pitfalls. Received: 22 February 2001/Accepted: 18 April 2001     

The role of mast cells and histamine in leukocyte-endothelium interactions in four rat strains

 The objective of the present study was to determine the role of mast cells and histamine in leukocyte-endothelium interactions in mesenteric venules of four rat strains: Brown Norway, Lewis, Sprague-Dawley and Wistar. Intravital microscopy showed that the mast cell stabilizer cromoglycate (5 mg/kg i.v. just before exteriorization of the mesentery) did not affect the baseline level and velocity of leukocyte rolling in any of the four strains. This finding is in agreement with the observation that cromoglycate pretreatment only slightly influenced mast cell degranulation in all strains except the Brown Norway. After mast cell stabilization, only in Sprague-Dawley did topical administration of histamine (10^–4 M) result in a significant increase in the level of leukocyte rolling and a decrease in the rolling velocity compared with the time control. Histamine induced leukocyte adhesion only in the Brown Norway strain. In conclusion, the hypothesis presented in other studies, that degranulation of mast cells, and more specifically the release of histamine, is of major importance for the induction of leukocyte-endothelium interactions in rat mesenteric venules is not generally applicable; the present study shows a clear strain dependency. Received: 18 July 1997 / Received after revision: 17 November 1997 / Accepted: 13 March 1998     

Pneumocystis carinii pneumonia associated with methotrexate therapy in rheumatoid arthritis

Opportunistic infections occur in patients with rheumatic diseases treated with low dose methotrexate (MTX) with or without other immunosuppressants. Our case report illustrates a fatal case of Pneumocystis carinii pneumonia in a patient with rheumatoid arthritis treated with low dose MTX and glucocorticoid. A review of the literature reveals other opportunistic infections such as Cryptococcus, Nocardia, and herpes zoster presenting in such patients. These occurrences suggest that MTX should be used cautiously in patients with rheumatic disease receiving concomitant medical therapy.     

Effects of bombesin and gastrin-releasing peptide on memory processing

We have previously shown that feeding mice immediately following training enhances memory retention and that one of the gastrointestinal hormones released during a meal, cholecystokinin, also enhances retention after peripheral administration. In the studies reported here we demonstrate that another gastrointestinal peptide, gastrin-releasing peptide (GRP), enhances retention after peripheral administration, as does its amphibian counterpart, bombesin. GRP_14–27 had the same effect as the intact peptide, while GRP_1–16 was ineffective at enhancing retention. The dose-response curves showed a characteristic inverted U-shape with high doses of both GRP and bombesin being amnestic. The effect of both peptides was time-dependent and both reversed amnesia induced by the anticholinergic, scopolamine. I.c.v. administration of the peptides required higher doses to produce an effect on memory retention. suggesting that the effect was mediated predominantly through a peripheral mechanism. Doses of the peptides that enhanced memory retention after peripheral administration failed to increase serum glucose, suggesting that glucose modulation was not the mechanism by which GRP and bombesin modulate memory processing. Vagotomy inhibited the memory-enhancing effects of both GRP and bombesin, suggesting that these peptides produced their effect by stimulating ascending vagal pathways. These studies, together with our previous study with cholecystokinin, suggest the existence of a gastrointestinal hormonal system, which is activated by the passage of food through the intestine, that enhances memory retention.     

Urethral function after chronic cauda equina lesions in cats. I. The contribution of mechanical factors and sympathetic innervation to proximal sphincter dysfunction

We investigated the contribution of mechanical and sympathetic neural factors to proximal urethral sphincter dysfunction in the cat after chronic sacral rhizotomy. Concomitant vesicostomy prevented a decrease in the urethral pressure profile measured three months post-rhizotomy. Sympathetic influences on basal urethral perfusion pressure were the same in neurally-intact and chronic rhizotomised cats. A significant prazosin-sensitive component of basal urethral perfusion pressure remained after section of all extrinsic urethral innervation in both neurally-intact and chronic cats. Local intra-arterial 6-hydroxydopamine also abolished this component. After rhizotomy, noradrenaline content in the proximal urethra was significantly increased but there was no change in sensitivity to sympathetic stimulation. A small (5% of control) atropine-sensitive and prazosin-resistant constriction was seen only after chronic sacral rhizotomy. We conclude that a mechanical factor associated with bladder expression and not an alteration in sympathetic control is the major factor leading to diminished proximal urethral closure after vesicourethral lower motor neuron lesion. Furthermore, short adrenergic neurons have an important role in the maintenance of urethral pressure in the normal state and after lower motor neuron lesion.     

The implementation of audit in an ENT unit

ENT Departments in the United Kingdom are faced with increasing pressure from government, management and the Colleges responsible for surgical training to introduce formal medical self audit. The plethora of guidelines and publications on the subject rarely address the differences in clinical practice between general medicine or surgery and that of otolaryngology. Clearly the lead in the introduction of medical audit will come from the appropriate specialist associations; however, this paper aims to share the experience of the implementation of audit in one otolaryngology, head and neck surgery unit and offer suggestions for a programme elsewhere.     

Assessment of the spatial occurrence of childhood leukaemia mortality using standardized rate ratios with a simple linear Poisson model.

Reports of a suspected cluster of childhood leukaemia cases in West Central Phoenix have led to a number of epidemiological studies in the geographical area. We report here on a death certificate-based mortality study, which indicated an elevated rate ratio of 1.95 during 1966-1986, using the remainder of the Phoenix standard metropolitan statistical area (SMSA) as a comparison region. In the process of analysing the data from this study, a methodology for dealing with denominator variability in a standardized mortality ratio was developed using a simple linear Poisson model. This new approach is seen as being of general use in the analysis of standardized rate ratios (SRR), as well as being particularly appropriate for cluster investigations.