Clinical Case Of the Month: A 35 Year Old Woman with Abdominal Pain.

A 35 year old woman with past medical history of hypertension presented to the emergency department with chief complaint of severe abdominal pain for one week. The abdominal pain was located in the epigastrium and described as "cramping" and "intermittent". The pain intensity was quantified initially as 6 out of 10 on the pain scale. As the week progressed the pain became constant and radiated to the back. The intensity of the abdominal pain increased to 10 out of 10. The patient reported some relief from her pain while lying in the prone position. Initially the pain was associated with loose stools for several days. The loose stools resolved spontaneously and then the patient began to experience nausea and vomiting. Her medications included lisinopril-hydrochlorothiazide which she had been taking for the past five months. She had no history of alcohol, tobacco or illicit drug use.

Development of a highly sensitive and specific carboxy-terminal human pancreastatin assay to monitor neuroendocrine tumor behavior.

OBJECTIVE: Pancreastatin is a fragment of the chromogranin A (CgA) molecule. Existing pancreastatin assays, which depend on antibodies that cross-react in varying percents with the larger prohormone, may lack sensitivity and specificity to detect small changes in neuroendocrine tumor volume. METHODS: We developed a highly specific, sensitive pancreastatin assay. The antibody used recognizes the carboxyl terminal of the peptide hormone and was raised against a 17-amino acid porcine pancreastatin fragment with high homology with the carboxy-terminal amino acids 286-301 of the human CgA. RESULTS: Our assay measures more than 95% of circulating pancreastatin levels; has little or no cross-reactivity with CgA, even at plasma concentrations of 1000 ng/mL; and can detect pancreastatin levels of 17 pg/mL. Interassay reproducibility for the pancreastatin radioimmunoassay was determined from results of 3 quality control pools in 15 consecutive assays. Coefficients of variation for low, medium, and high pancreastatin levels were less than 20%. The sensitivity of serial pancreastatin assays to detect early liver tumor activity was demonstrated in 2 patients with slowly progressive neuroendocrine tumors and in patients undergoing surgical cytoreduction. CONCLUSIONS: This highly specific, sensitive pancreastatin assay can detect small changes in liver tumor progression and is up to 100-fold more sensitive and specific than CgA assays in the United States.