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R Chartrand

Publications and source records attributed to R Chartrand.

At least 37 records · Page 2Linked to original sources

Abdominal patterns of indium-111 labeled leukocyte imaging.

In-111 oxine WBC abdominal scanning is now a widely accepted technique for the detection of abdominal infectious processes. High sensitivity and specificity are achieved. In-111 labeled leukocyte accumulation, however, does not always suggest the diagnosis of abscess. Higher specificity could be obtained by the knowledge of the In-111 leukocyte distribution pattern in the abdomen in other pathologic states like inflammation of abdominal wounds, stoma; surgical complication without abscess formation; inflammatory or ischemic bowel disease; or swallowing leukocytes which subsequently are visualized in the intestinal lumen. One hundred fifty-two consecutive WBC scans performed over 18 months were reviewed and classified according to their pattern of uptake: 96 cases showed no abdominal uptake, and 56 had accumulation of leukocytes in the abdomen. Twenty-eight of these patients had proven abdominal abscess, and the remaining 26 were positive due to other causes. This report briefly discusses the distribution pattern of In-111 labeled leukocytes in the latter patients and compares the results obtained using different diagnostic criteria.

Abdomen↗

Characteristics of patients with normal T3 and T4 and a low TSH response to TRH.

The nature of the thyroid disorder presented by patients with normal T4 and T3 but blunted TSH response to TRH has not been clarified. In this study, we compared thyroid function tests in 16 such patients with those of 14 controls and 10 hyperthyroid patients. Basal total T4, free T4, total T3, iodine uptake and cholesterol of the study group were similar to controls but significantly (P less than 0.001) lower than in hyperthyroid patients, except for cholesterol which was higher. In contrast, the basal TSH, increase in TSH after TRH stimulation, and decrease of T4 during T3 suppression tests were similar to data obtained in hyperthyroid patients but significantly (P less than 0.001) lower than in controls. Pulse rate was mid-way between the control and the hyperthyroid group. Thyroid stimulating antibody (TSAb) was measured with human thyroid cells in culture; the assay was positive in four subjects in the 16-patient group and in all hyperthyroid patients tested. TSH stimulation test showed a hyporesponse in iodine uptake in the four patients with positive TSAb (26 +/- 29%), as well as in hyperthyroid patients (6 + 5%). However, there was a hyper-response to TSH (213 +/- 52%) in the remaining 12 patients in the group, none of whom had TSAb. Thus TSAb is not seen as responsible for the thyroid disorder in the majority of patients with normal T3 and T4 and absent or blunted TSH response to TRH; surprisingly, most of these patients have thyroid hypersensitivity to TSH. These two characteristics, absence of TSAb and hypersensitivity to TSH, delineate a thyroid disorder clearly different from Graves' disease.

Adult↗

The pituitary-thyroid axis after hemithyroidectomy in euthyroid man.

The pathogenesis of euthyroid goiter is assumed to be TSH dependent, but most studies have not demonstrated elevation of serum TSH. To elucidate the early events involved in thyroid growth, we studied thyroid function in eight euthyroid patients subjected to hemithyroidectomy for solitary cold nodules preoperatively and 2, 15, 60, and 90 days and 36 months, postoperatively. Although within the euthyroid range, serum T4 decreased at 30 days and thereafter up to 90 days (P less than 0.01). Basal serum TSH rose significantly by the 30th day and remained elevated for the entire 90-day period (P less than 0.001). The serum TSH response to TRH was exaggerated from days 15-90 (P less than 0.001). Thirty-six months postoperatively, all parameters of thyroid function were similar to control values, with the exception of one patient who showed an exaggerated response of serum TSH to TRH. We conclude that 1) the dynamic phase of recuperation post hemithyroidectomy is TSH dependent, 2) the serum TSH increase occurs within normal limits and is a temporary event, and 3) 3 yr postoperatively, a new steady state is achieved with normal parameters of thyroid function. Thus, we believe that TSH plays a dominant role in the genesis of goiter.

Adult↗

Extrahepatic uptake of 99mTc-phytate: its mechanism and significance in chronic liver disease.

The extrahepatic uptake of 99mTc-phytate was evaluated using scintigrams in 47 patients, including 37 patients with cirrhosis, 7 with presinusoidal portal hypertension, and 3 with idiopathic splenomegaly. In these 47 patients, combined umbilicoportal, hepatic vein, and superior mesenteric artery catheterization was performed. The Kupffer cell uptake of 125Iodinated albumin microaggregates was measured during a single passage through the liver, and this parameter was used as an index of the functional hepatic blood flow. A highly significant negative correlation was found between the extrahepatic uptake of 99mTc-phytate and the hepatic uptake of 125I-albumin microaggregates. However, no correlation was found between the extrahepatic uptake and portal hypertension as evaluated by the porohepatic gradient. The present study strongly suggests that the 99mTc-phytate extrahepatic uptake is mainly due to a failure of the diseased liver to remove colloids and is not related to the degree of portal hypertension. Our data also indicate that 99mTc-phytate liver scan may provide an indirect assessment of the functional hepatic blood supply and might be useful in the follow-up of patients with chronic liver diseases.

Adult↗