Imaging features of rare pancreatic tumors.

The increasing use of abdominal imaging has led to a growing incidence of traditionally uncommon pancreatic tumors. These rare tumors have specific imaging features whose knowledge may heighten confidence in characterization and may avoid unnecessary surgical procedures when imaging findings suggest a benign condition. Computed tomography (CT) is the modality with which rare pancreatic tumors are incidentally detected in the majority of cases. Magnetic resonance imaging (MRI) is often performed as a second line examination for further characterization. This review provides an update on CT and MRI findings of rare tumors of the pancreas.

A solitary uterine relapse in T-cell Acute Lymphoblastic Leukaemia: CT features and pathologic correlation.

T-cell Acute Lymphoblastic Leukemia (T-cell ALL) is a rare haematological neoplasia, that affects children and less commonly adults. Female genital tract and particularly uterus involvement in acute ALL is rare. This report presents the CT features of a 64-year-old woman with uterine relapse of T-cell ALL, occurring 11 months after the diagnosis, as a second, unique relapse of disease. The patient was asymptomatic when a CT examination showed a homogenous thickness of the uterine wall in comparison with the previous CT examination. Histology from biopsy specimens, obtained through hysteroscopy, confirmed T-cell ALL localisation (TdT+, CD10+, CD3c+ and CD2+). The uterus could be a site of relapse in patients suffering from ALL. Even though an MRI examination could better demonstrate the disease in cases of suspected female genital tract involvement by ALL, the comparison of differences between a present and a previous CT examination is sufficient to suspect the diagnosis.

Abrupt-onset oculomotor paralysis: an endocrine emergency.

Pituitary apoplexy is a severe and potentially life-threatening condition that may be highly variable in its clinical presentation. We report a 37-year-old man presenting to the emergency department with diplopia that abruptly developed while he was eating canned and bottled food prepared at home. A computed tomography scanning revealed an isodense mass within the sellar region and, subsequently, a magnetic resonance imaging showed a pituitary apoplexy causing a compression of the right III and VI oculomotor nerves. There was no improvement with hydrocortisone therapy and the patient underwent a transsphenoidal excision of the mass with an uneventful course. Pituitary apoplexy may raise in the appropriate setting the suspicion of botulism. The abrupt-onset paralysis of oculomotor nerves has been described as the chief presenting sign of pituitary apoplexy in only few cases including this. A pathophysiology, differential diagnosis with botulism and other causes of multiple cranial nerve paralysis, and treatment are described.

Fulminant purpuric rash.

We report on a fatal case of purpura fulminans caused by severe meningococcaemia. Despite early and aggressive treatment with the use of a specific algorithm and the maintenance of a stable haemodynamic status in the first hour since admission, purpura fulminans developed impressively over a few minutes. Necropsy showed microvascular thrombosis in the dermis but not in visceral organs, suggesting the diagnosis of meningococcal septic shock with purpura fulminans limited to the skin. Acquired deficiency of protein C, which exerts anticoagulant and antiinflammatory functions, is the central mechanism ultimately responsible for purpura fulminans. The disorder predicts a poor outcome of meningococcaemia and early and aggressive resuscitation is recommended in the emergency department with antibiotics, volume expansion, inotropic drugs, and protein C replacement. An attitude of scepticism is appropriate in the management of these patients even when early resuscitation is successful and haemodynamic parameters remain stable.

Intraluminal pH and oesophageal motility in patients with gastro-oesophageal reflux.

The effect of intraluminal pH on motor activity of the lower oesophageal body was studied in patients with pathological gastro-oesophageal reflux. Liquid boluses with a pH range of 6.98-1.1, infused in the distal oesophagus of 21 patients during manometric recording of motor activity, elicited either secondary peristalsis or simultaneous contractions. Acid pH did not affect the threshold of distension required to elicit secondary peristalsis. Oesophageal responses to volumes of instillate did not differ in patients with normal and abnormal acid clearing test, nor in patients with a negative and positive acid perfusion test.

Effect of bombesin on lower esophageal sphincter pressure in humans.

Intravenous infusion of bombesin in humans results in increased serum gastrin levels and increased lower esophageal sphincter pressure. To differentiate a gastrin- from a nongastrin-mediated mechanism, the effect of intravenous bombesin infusion on lower esophageal sphincter pressure was studied in 5 healthy subjects and in 5 antrectomized patients. Lower esophageal sphincter pressure was recorded by three continuously perfused catheters with side-openings located 5 mm apart. Blood samples were taken at regular intervals during the study periods to assay gastrin and pancreatic polypeptide. Manometric tracings and blood samples were coded and evaluated blindly. Lower esophageal sphincter pressure increased during bombesin infusion both in normal and antrectomized subjects. The increase had a delayed onset and persisted after discontinuation of bombesin. No correlation was found between lower esophageal sphincter pressure and serum gastrin or pancreatic polypeptide values. These data indicate that the effect of bombesin on lower esophageal sphincter pressure is not gastrin or pancreatic polypeptide mediated.

Lower oesophageal sphincter response to intravenous infusions of pentagastrin in normal subjects, antrectomised and achalasic patients.

Lower oesophageal sphincter response to infusion of graded doses (0.003--0.050 microgram kg-1min-1) of pentagastrin was evaluated in four antrectomised patients as well as in six healthy subjects and seven achalasic patients in whom inhibition of antral gastrin release was maintained by continuous acidification (HC1 0.1 N) and aspiration of gastric antrum. In normal subjects and in antrectomised patients doses of pentagastrin required for half-maximal gastric acid secretion (0.012 microgram kg-1min-1) produced statistically significant increases of LES pressure. In achalasic patients, the infusion of pentagastrin did not affect LES pressure. These data seem to indicate that gastrin plays, at least in some degree, a physiological role in the regulation of LES tone. Insensitivity of LES to pentagastrin in achalasia suggests that the raised sphincter pressure in this disorder can not be attributed to gastrin.

Intraluminal pH esophageal motility.

The aim of the present study was to investigate the effect of intraluminal pH on motor activity of the lower esophageal body. Liquid boluses of different pH values (7 to 2) were infused in the esophagus of 14 normal subjects during manometric recording of motor activity. Each test infusion elicited an esophageal motor response, either secondary peristalsis or simultaneous contractions. Secondary peristalsis was elicited by similar volumes of perfusates at pH 7, 6, 5, but significantly less volumes were needed with perfusates pH 4, 3, and 2. Simultaneous motor activity was not affected by intraesophageal pH value in the range investigated.