A case of intractable nausea and vomiting following posterior fossa craniotomy

We describe a unique case of prolonged nausea and vomiting following posterior fossa craniotomy for removal of a meningioma. No apparent neurological or gastrointestinal causes were discovered except for a delayed gastric emptying time. The symptoms gradually resolved along with normalization of the gastric emptying time. Possible pathogenic mechanisms are discussed.

Ascorbic acid absorption in patients with systemic sclerosis

OBJECTIVE

To investigate whether reduced circulating levels of ascorbic acid in patients with systemic sclerosis (SSc) are a result of malabsorption.

METHODS

Eight patients with SSc, but with no evidence of bacterial overgrowth, and 8 healthy controls were recruited. On the first day of study, each subject was given orally an aliquot of [14C] ascorbic acid, which was then "flushed out" by oral intake of unlabeled ascorbic acid for the following 7 days. Plasma samples were collected at specified intervals and urine was collected continuously over the 8 day study period. [14C] content of plasma and urine were measured by scintillation counting. For each subject, a plasma [14C] decay curve was drawn. Each subject's ascorbic acid absorption was assessed using the area under the curve (AUC) and the apparent renal clearance (CLr[app]). Ascorbic acid intake was assessed using dietary history and food composition tables.

RESULTS

There were no differences in the dietary intake of vitamin C (p = 0.16) and body mass indices (p = 0.91) between patients and controls. The plasma [14C] AUC and CLr(app) were similar between patients and controls [AUC patient mean (standard deviation, SD) = 37.1 (6.8), AUC control mean (SD) = 38.6 (9.9), p = 0.74; CLr(app) patient mean (SD) = 0.57 (0.24), CLr(app) control mean (SD) = 0.47 (0.27), p = 0.45].

CONCLUSION

There was no evidence of impaired absorption of ascorbic acid in patients with SSc without bacterial overgrowth compared to healthy controls.

Ascorbic acid absorption in Crohn's disease. Studies using L-[carboxyl-14C]ascorbic acid

Total body pool and intestinal absorption of ascorbic acid were studied in 12 patients undergoing operation for Crohn's disease (six with fistulae and six without) and in six control patients undergoing operation for reasons other than Crohn's disease. L-[carboxyl-14C]Ascorbic acid, 0.19-0.40 megabecquerels (MBq), was given orally. After a period of equilibration, the labeled ascorbic acid was flushed out of the patient's body tissues using large doses of unlabeled ascorbic acid. Intestinal absorption of ascorbic acid, assessed from the total cumulative urinary 14C recovery, was found to be similar in patients with fistulizing Crohn's disease (73.9 +/- 8.45%), those without fistulas (72.8 +/- 11.53%), and in controls (80.3 +/- 8.11%). Total body pools of ascorbic acid, calculated using the plasma 14C decay curves, were similar in patients with Crohn's disease with fistulas (17.1 +/- 5.91 mg/kg), patients without fistulas (9.6 +/- 3.58 mg/kg), and in controls (13.3 +/- 4.28 mg/kg). The results indicate that ascorbic acid absorption is normal in patients with both fistulizing and nonfistulizing Crohn's disease. The results suggest that routine supplements of vitamin C are not necessary unless oral ascorbic acid intake is low.