Leo V. dos Remedios

Detecting Unsuspected Thyroid Dysfunction by the Free Thyroxine Index

The free thyroxine index (FTI) was used in 2,704 adults to detect unsuspected thyroid dysfunction. Among 2,581 adults found to be clinically euthyroid without thyroid medication, 2,571 had a truly normal FTI (121 to 360) and ten had a falsely abnormal FTI (seven less than 121, three greater than 360). Among 25 subjects with newly diagnosed thyroid dysfunction, there were eight hyperthyroid (prevalence, 0.31%) and 14 hypothyroid (prevalence, 0.50%) subjects. The sensitivity of the FTI was 1.0, and the specificity was 0.996. The predictive value of an abnormal FTI with a prevalence of 0.81% was 67%. The cost to find a new case averaged

Heterogeneity of congenital primary hypothyroidism: The importance of thyroid scintigraphy

127. The annual incidence of symptomatic hyperthyroidism was 0.05%; of hypothyroidism, about 0.08%. We conclude that the FTI is cost-effective for case finding in thyroid dysfunction.

Diagnosis of acute cholecystitis using hepatobiliary scan with technetium-99m PIPIDA

Current newborn screening programs in California and most of the U.S. depend for diagnosis of congenital primary hypothyroidism on demonstrating an elevated thyrotropin (TSH) level in infants with the lowest 5% to 10% of thyroxine (T4) levels by filter-paper bloodspot test. The diagnosis of primary congenital hypothyroidism based on low T4 with high TSH fails to distinguish between transient hypothyroidism, ectopic or hypoplastic thyroid, athyrosis, dyshormonogenesis, and transient hyperthyrotropinemia. We screened 166,300 newborn infants for primary congenital hypothyroidism for 6.5 years and confirmed the diagnosis in 46 cases; none of these patients had a goiter. Thyroid scintigraphy was performed in 40 with technetium-99m (Tc-99m) in the first eight cases tested and iodine-123 (I-123) in 29 of the last 32 cases. Fifteen infants were athyroid and seven had ectopic or hypoplastic glands; in 18 the thyroid gland appeared normal (present, normal location). Congenital hypothyroidism represents a spectrum of diseases from transient underactivity to complete absence of the thyroid gland. We recommend that, before starting treatment, a specific anatomic and functional diagnosis be confirmed by thyroid scintigraphy and other thyroid function tests.

The importance of perfusion imaging in brain scintigraphy for subdural hematoma.

Sixty patients were evaluated for acute abdominal pain using technetium-99m PIPIDA hepatobiliary imaging. The sensitivity of the test was 90.6 percent in all patients and the accuracy was 93.3 percent. In the evaluation of acutely ill patients with right upper quadrant pain, fever, nausea and vomiting, hepatobiliary imaging with PIPIDA is the preferred test for diagnosing acute cholecystitis. If the test is positive, disease of the gallbladder and probably acute cholecystitis are present. Early operation can proceed if desirable. If the test is negative and the bilirubin level is less than 5.0 mg/dl, acute cholecystitis is not present. In such cases conservative treatment is appropriate, and follow-up tests should be performed to evaluate the possibility of chronic cholecystitis. When the bilirubin level exceeds 5.0 mg/dl, the test is often indeterminate.

Radioimmunoassay for herpes simplex virus.

The authors report a case of subdural hematoma in a patient who showed bilateral perfusion defects, highly characteristic of subdural hematoma, but did not show the expected complementary static abnormalities. This appears to be the first such case in the literature.

Dynamic/Static Brain Scintigraphy in Neonates

Radioimmunoassay has been used for time in the detection of the Australia Antigen. In this experiment, radioimmunoassay with Iodine-125 (125I) permitted rapid detection of the presence of herpes simplex virus, type I, in vitro. This is a convenient technique for the detection of virus, which now requires laborious methods involving observation for the cytopathic effect of virus upon cultured cells.

INDIUM LABELED LEUKOCYTES FOR ACUTE APPENDICITIS DETECTION

In order to acquaint physicians caring for newborn babies with the value of complementing static brain scintigraphy with the dynamic brain blood perfusion study, cases of intracerebral hemorrhage, cerebrovascular anomaly, and cerebral malformation are presented. This screening procedure is not only a safe, simple, quick adjunct to the clinical diagnostic impressions, but may on occasion obviate the need for the more precise, but more formidable, procedures of contrast angiography and pneumoencephalography.

Renal Cortical Imaging in 35 Patients: Superior Quality with 99mTc-DMSA

We report the successful use of Indium-111 labeled leukocytes to make the diagnosis of acute appendicitis. Clinical diagnosis has a false positive rate of approximately 20%. This has been accepted as the national standard to prevent the complication of ruptured appendix and peritonitis. Patients who present to the E.R. with symptoms and signs of possible appendicitis were screened by the surgical service and those with clear-cut appendicitis went to surgery. Those assigned to observation as possible but not definite acute appendicitis were selected for study. Using standard methodology leukocytes were harvested, labeled, and re-injected. Imaging was done at 2 hours. Scans were interpreted as supportive of the diagnosis or non-diagnostic. Surgical specimens were imaged to document the presence of Indium-111. Of 11 patients studied, there were 5 with positive scans all of whom had acute appendicitis proven at laparotomy. One non-diagnostic exam eventually went to laparotomy where a necrotic appendix was found. This patient had been an in-patient on I.V. antibiotics. Scan of the surgical specimen showed good labeling of the appendix. Four patients had negative early scans and were not operated on. One scan consistent with peritonitis without localized accumulation of tracer had this diagnosis confirmed at laparotomy. We have found that positive scans correlate well with acute appendicitis. Negative scans correlate well with negative pathology. Our 1 false negative so far indicates that this test may not be useful for cases where I.V. antibiotics have been used and delayed imaging is necessary.