Ectopic ACTH syndrome due to thymic carcinoid tumor in a girl

An 8 year-old girl had a cushingoid appearance for six months. Hormone study showed extremely high serum levels of cortisol (> 60 micrograms/dl) and adrenocorticotropic hormone (930 pg/ml). Initial chest X-ray showed nothing unusual, but a technetium-99mm MIBI scan showed an accumulation lesion in the left upper chest cavity. Chest magnetic resonance imaging demonstrated that the mass was in the superior anterior mediastinum. She had complete removal of the tumor with partial thymectomy. The pathology revealed a thymic carcinoid tumor. Carcinoid tumors of the thymus are extremely rare in children and they usually present with Cushing's syndrome. To our knowledge, this is the youngest patient who has ever been reported with this disease.

Preparation of poly(acrylic acid) modified polyurethane membrane for biomaterial by UV radiation without degassing

Poly(acrylic acid) modified polyurethane (AA/PU) membranes were prepared by UV radiation without degassing. The chemical composition of the AA/PU membrane was studied by IR spectroscopy. In addition to those absorption peaks associated with pure PU, the absorption peak at 2400 cm-1 of poly(AA) was also found. The morphology of AA/PU membrane was studied by optical polarizing microscopy. We also measured the glass transition temperature and the decomposition temperature of the AA/PU membrane by differential scanning calorimetry and thermogravimetric analysis. A significant domain was found in the AA/PU membrane, which resulted in different glass transition temperature and decomposition temperature between AA/PU and pure PU membrane. The effect of AA content on the contact angle and water absorption of the AA/PU membrane was determined. It was found that the water content of AA/PU membrane increased with increasing AA content, whereas the contact angle decreased. By using Kaeble's equation and the contact angle data, the surface free energy of AA/PU membrane was determined. The increase of surface free energy resulted from the increase of the dispersion (gammad) term and polar (gammap) term. In order to evaluate the biocompatibility of these membranes, a cytotoxicity test and a cell adhesion and proliferation assay were conducted in cell culture. Immortal cells and primary lymphocytes were both used in this study. The results showed that these AA/PU membranes exhibited very low cytotoxicity and could support cell adhesion and growth. An animal primary test was also done in this study. It was found that the AA/PU membrane could possibly be employed in the treatment of bowel defect.

Prevalence and significance of thyroid autoantibodies in patients with chronic hepatitis C virus infection: a prospective controlled study

OBJECTIVE

To clarify controversies on the prevalence and clinical significance of thyroid autoimmunity in hepatitis C virus (HCV) infection.

DESIGN

A prospective controlled and follow-up study.

PATIENTS AND MEASUREMENTS

Serum thyroid microsomal antibody (TMA) and thyroid stimulating hormone were assayed and compared in a consecutive, unselected series of 130 patients with chronic HCV infection, 130 sex/age (+/- 2 years)-matched patients with chronic hepatitis B virus (HBV) infection and 260 matched normal controls.

RESULTS

The prevalence of thyroid autoantibodies in male patients with chronic HCV was < 2%. The prevalence of TMA (< 1:400) in female patients with chronic HCV infection was significantly higher than that of HBV controls (22.1 vs. 1.6%; P < 0.001), and higher but not significant compared with normal controls (13.5%). However, the trend of increasing prevalence with age in normal controls was not observed in HCV patients. TMA seropositive female HCV patients were not different from seronegative counterparts in age, duration of infection, HLA haplotype, associated autoantibodies and liver histology but had a significantly higher prevalence of genotype 1b/2b mixed infection (P < 0.01) and anti-GOR (P < 0.05). Of the 23 HCV patients seropositive for thyroid autoantibodies, seven had Hashimoto's thyroiditis, two had Graves' disease and three had received subtotal thyroidectomy. During follow-up, four of 15 female patients showed a 14-16-fold increase in TMA titre and one developed hyperthyroidism. Patients with thyroid autoantibodies did not show a propensity to develop thyroid dysfunction during interferon therapy.

CONCLUSIONS

These results suggest a weak association between HCV and thyroid autoimmunity in females. As in the ordinary population with thyroid autoantibodies, they should be evaluated for thyroid status and be followed-up if thyroid autoimmunity is evident. However, seropositivity of thyroid autoantibodies is not a contraindication to interferon therapy.

Surgical treatment of severe perthes disease: comparison of triple osteotomy and shelf augmentation

The optimal management of the severe form of Perthes disease is controversial. This retrospective study evaluated the results of two procedures in two groups of patients with Perthes disease. The Catterall classification was adopted for grouping of patients before treatment. The Herring classification was used for comparison of the follow-up radiographs. Under the concept of surgical containment, triple innominate osteotomy was performed in 14 patients at an average age of 8 years 7 months with a mean follow-up period of 4 years 3 months. Staheli's shelf augmentation was performed in 14 patients at an average age of 10 years 2 months with a follow-up period of 3 years 8 months. Radiologically, femoral head subluxation, acetabular coverage, acetabular angle, and center-edge angle were markedly improved in both groups. In the clinical evaluation using modified Sundt's criteria, both procedures were effective. Satisfactory results were achieved in 79% of 14 patients (5 good, 6 fair, and 3 poor) in the triple osteotomy group, and 100% of 14 patients (two good, 12 fair) in the shelf augmentation group. Nevertheless, triple innominate osteotomy is technically more demanding with a longer operating time and resulted in more complications. Staheli's shelf augmentation is a simpler procedure with better coverage of the acetabulum. However, asphericity of the femoral heads was observed more frequently in this group. The Herring lateral pillar classification was better than the Catterall classification in predicting the final outcomes in this study.

Papillary and follicular thyroid carcinomas with bone metastases: a series of 39 cases during a period of 18 years

BACKGROUND

Bone metastases can cause death in patients with papillary or follicular thyroid carcinoma. There is, however, limited information about the clinical presentations and prognoses of patients with papillary and follicular thyroid carcinomas with bone metastases in Taiwan.

MATERIALS AND METHODS

A series of 39 patients with papillary or follicular thyroid carcinomas with bone metastases treated at our center from 1977 through 1995 was retrospectively reviewed to elucidate the clinical presentations and results of treatment of this disease.

RESULTS

The occurrence rate of bone metastasis in papillary and follicular thyroid carcinomas was 4.3%. Of the 39 patients, whose mean age was 57.5 years, 28 (71.8%) had follicular and 11 (28.2%) had papillary carcinomas. Thirty-two patients (82.1%) were female and 7 (17.9%) were male. Twenty-nine patients (74.4%) presented with bone metastases before the thyroid cancers were diagnosed. Bone metastases were detected using radiography in 33 patients and using 131I scans in 28 patients. Thirty-one patients (79.5%) had multiple bone metastases. The spine was the most frequently involved site (53.8%). Three patients were disease-free and 14 patients died during the course of treatment. Using the Kaplan-Meier method, the 5-year survival rate was estimated to be 64.9%.

CONCLUSION

Bone metastasis, although rare in patients with papillary carcinoma, was not very uncommon in patients with follicular carcinoma. Bone metastases occurred more often in older patients. Multiple bone metastases were noted more often than single bone metastasis. Most patients had symptoms and signs resulting from metastatic bone lesions. Although multimodality therapy was tried, the prognoses for most patients with bone metastases were poor.

Relative value of thallium-201 and iodine-131 scans in the detection of recurrence or distant metastasis of well differentiated thyroid carcinoma

Radioactive iodine (131I) has been found to be more sensitive and more specific than thallium-201 for the detection of distant metastases and thyroid remnants in the neck in cases of well-differentiated thyroid carcinoma. 201Tl has been deemed particularly useful in localizing metastases or recurrence in patients with a negative 131I scan and abnormal levels of serum thyroglobulin (Tg). This study aimed to: (1) determine the value of 201Tl imaging in localizing metastases or recurrence in patients with well-differentiated thyroid carcinoma, and (2) evaluate the false-positive and false-negative results of 131I and 201Tl scintigraphy. Sixty-two thyroid remnant ablated patients who underwent simultaneous postoperative 201Tl and 131I scans and and serum Tg determinations were evaluated. Fifty patients had papillary thyroid carcinomas and 12 had follicular thyroid carcinomas. 201Tl imaging was performed before the 131I studies. Of the 62 patients who underwent 201Tl imaging studies, 24 were found to have positive results, with local recurrence or distant metastases. Patients with positive results in the 201Tl imaging studies tended to be older, were mor often male, had higher Tg levels and had a higher recurrence rate. Of these 24 patients, ten had negative diagnostic or therapeutic 131I scans. Concurrently, serum Tg levels were less than 5 ng/ml in five of these ten patients. Three patients were deemed false positive by 201Tl scans; one had a parotid tumour, one a periodontal abscess and one lung metastasis. Among the 38 patients with negative 201Tl scans, 11 had positive findings on 131I scans. Three had distant metastases: two with lung metastases and one with bone metastases. Patients with false-positive results on 131I scans included those with biliary tract stones, ovarian cysts, and breast secretion. Of the 27 patients with negative 201Tl and 131I scans, 15 had elevated serum Tg levels. Among these, local recurrence followed by lung metastases was manifested in a 49-year-old male with papillary thyroid carcinoma. In conclusion, both 131I and 201Tl scans are useful in the detection of recurrence or distant metastasis of well differentiated thyroid cancers. 201Tl scan could in particular be used in patients with a negative 131I scan in conjunction with an elevated Tg level.

Endocrinological aspects of Langerhans cell histiocytosis complicated with diabetes insipidus

Langerhans cell histiocytosis (LCH) is a rare disorder and may be complicated with hypopituitarism and diabetes insipidus (DI) due to invasion of the hypothalamic-pituitary area. In this study, 10 patients with complete (4) and partial (6) type central DI were found among 125 LCH patients in our hospital records. The water deprivation test, followed by the pitressin test, was performed to confirm DI. Hypothalamic-pituitary endocrine function tests were carried out on these 10 patients at the initial diagnosis and during follow-up. All patients revealed growth hormone insufficiency in the insulin hypoglycemic tolerance test. Four patients had impairment of cortisol secretion, demonstrated by insulin hypoglycemic stimulating test results. Two patients had poor response in the thyrotropin releasing hormone stimulating test. Two patients had only partial responses in the luteinizing hormone releasing hormone test. Four patients had hyperprolactinemia. All patients underwent surgical treatment followed by chemotherapy and/or radiotherapy. One patient completely recovered from the endocrine disorder, 3 patients required smaller doses of desmopressin, and one patient had normal adrenal, thyroid, and gonadal function. Hypothalamic-pituitary disorders in LCH should not be neglected. Treatment of LCH can partially or completely reverse associated endocrine disorders. Therefore, endocrine studies and hormone replacement should be mandatory for patients with LCH.

Content of reduced glutathione and consequences in recipients of glucose-6-phosphate dehydrogenase deficient red blood cells

The red blood cell glucose-6-phosphate dehydrogenase (G6PD) activity of every donor was examined with automatic enzyme-coupled method. The technique of molecular biology was applied to determine the DNA mutations for the 97 donors with undetectable G6PD activity. The concentration of reduced glutathione (GSH) in the stored RBC of the 97 G6PD-deficient donors and 124 normal donors was determined with the technique of high performance liquid chromatography. Routine blood counts, bilirubin and haptoglobin levels were used to evaluate posttransfusional hemolysis for the 48 adult patients transfused with 1 U G6PD deficient and 1 U normal RBC. Most (88, 90.7%) of the 97 donors were confirmed to be G6PD deficient at the DNA level. At each age interval of storage, the GSH concentration of G6PD-deficient RBC was significantly different from that of normal RBC. The total average value of GSH (pmol/gHb) was 2.52 +/- 0.95 (mean +/- 1 standard deviation) vs. 3.74 +/- 1.43 (P < 0.001). Hemoglobin, hematocrit, bilirubin, and haptoglobin levels in the patients receiving G6PD-deficient RBC were not statistically different from those in the recipients of normal RBC; even though the age of stored blood was 26-35 days. Within the same group of patients, the results of bilirubin and haptoglobin were not significantly changed before and after transfusion. The results of this study show that the GSH concentration in the stored blood of G6PD deficient donors was 67% of that in the normal donors. However, hemolysis does not occur in adult patients transfused with 1 U G6PD-deficient RBC. It seems unnecessary to screen G6PD activity for donors of adult recipients in Taiwan.

Use of radioactive iodine for thyroid remnant ablation in well-differentiated thyroid carcinoma to replace thyroid reoperation

Complete thyroidectomy was recommended for patients with well-differentiated thyroid carcinoma to remove any potential residual contralateral cancer tissue and to facilitate detection of metastatic lesions by radioactive iodide (131I). Unfortunately, 8-32% incidence of severe complications were noted after reoperation. At present, there are still not enough data about the ablative effect of 131I for such conservative surgical treatment of well-differentiated thyroid cancers. The major goal of the present study was to examine the effects of 311I for ablation of thyroid remnants in order to obviate the severe complications associated with reoperation. From January 1977 to December 1995, 210 papillary or follicular thyroid carcinoma patients received subtotal thyroidectomy or lobectomy. After the operation, 46 of the 210 patients received 131I for remnant ablation. At doses of > or = 30 mCi 131I, 38 thyroid remnants were successfully ablated; 25 of 38 (65.8%) patients successfully ablated patients received 30 mCi 131I one-four times. Five patients expired during the follow-up period, including two follicular carcinoma patients who were misinterpreted as having benign lesions in the first operation. Patients in the overall failure versus success group for thyroid remnant ablation revealed increased age, histopathology of follicular carcinoma, higher postoperative 131I uptake in the neck bed, higher postoperative thyroglobulin levels, bigger tumor size, and higher mortality. In conclusion, repeated 30 mCi 131I treatments were adequate for most thyroid remnant ablations following subtotal thyroidectomy or lobectomy in well-differentiated thyroid cancer patients. Misinterpretation of follicular cancer as benign lesions and unresectable tumor comprised the main reasons for mortality.

Acute suppurative thyroiditis and aggressive malignant thyroid tumors: differences in clinical presentation

BACKGROUND AND OBJECTIVES

Aggressive malignant thyroid tumors (AMTT) may mimic the clinical symptoms and signs of acute suppurative thyroiditis (AST) in the early course of the disease process. Our objective was to analyze the clinical features of these two conditions, to assess the best way of early diagnosis, and to propose proper treatment.

METHODS

We retrospectively reviewed and analyzed the clinical features of 30 patients, who had similar clinical pictures of AST and were managed at Chang Gung Memorial Medical Center in Linkou, Taiwan, during the period from 1983 to 1996. These patients were consequently diagnosed as either AST or AMTT. The data were analyzed by the Mann-Whitney U, chi-square and Fisher's exact tests.

RESULTS

Among the 30 patients, 25 patients (Male/Female (M/F) ratio = 9/16) were diagnosed as having AST and 5 (M/F ratio = 1/4) as AMTT. After statistical analysis we concluded that the presence of the following factors, namely, older age at diagnosis (P = 0.0155), history of dysphonia (P = 0.0325), right thyroid lobe involvement (P = 0.0151), large size of lesions (P = 0.0013), presence of anemia (P = 0.0075), and sterile pus cultures from thyroid aspirates (P = 0.0013) were cause to suspect a malignancy if the condition did not improve after antibiotics. Delay in diagnosis and management of AMTT may result in a poor prognosis (P = 0.0082).

CONCLUSION

Due to the high mortality rate of AMTT, we should closely observe the patients with poor prognostic variables of acute thyroiditis. Earlier detection and aggressive surgical intervention for AMTT might improve the outcome.

Computer-assisted design of new drugs based on retrometabolic concepts

Retrometabolic drug design approaches incorporate metabolic and toxicological considerations into the drug design process and represent a novel, systematic methodology for the design of safe compounds. Two major design concepts aimed to increase the therapeutic index (the activity/toxicity ratio) of drugs were developed. Chemical delivery systems (CDS) are primarily used to allow targeting of the active biological molecules to specific target sites or organs based on predictable enzymatic activation. Soft drug approaches are used to design new drugs by building in the molecule, in addition to the activity, the most desired way in which the molecule is to be deactivated and detoxified subsequent to exerting its biological effects. Special computer programs were developed that starting from a lead compound generate complete libraries of possible soft analogs and then help ranking these candidates based on isosteric-isoelectronic comparisons, predicted solubility/partition properties, and estimated metabolic rates. The novel field of large peptide-CDSs imposes special challenges, but a new, remarkably simple model was developed to estimate partition properties for a wide range of compounds, including quite large peptide derivatives. A suggested change of about five order of magnitudes in the distribution coefficient can explain the "lock in" mechanism of brain-targeting delivery systems.

Two novel glucose 6-phosphate dehydrogenase deficiency mutations and association of such mutations with F8C/G6PD haplotype in Chinese

Glucose 6-phosphate dehydrogenase (G6PD) deficiency is a common genetic disease affecting 3% of the total Chinese population in Taiwan. To investigate the molecular basis of this deficiency, we analyzed blood samples from G6PD-deficient newborns using a nonradioactive polymerase chain reaction coupled with single-stranded conformation polymorphism (PCR-SSCP) analysis. We identified two novel G6PD mutations in Chinese. The first, G6PD Miaoli, involved a C-->G substitution at nucleotide (nt) 519, producing a Phe173 to Leu change in the protein. The second mutation (G6PD Keelung) involved a C-->T change at nt 1387, resulting in an Arg463 to Cys substitution. The F8C/G6PD (coagulation factor VIIIc) haplotype that spans the Xq28 region from the gene for coagulation factor VIIIc to the gene for G6PD was also investigated in Chinese using PCR and restriction enzyme digestion. Of the 16 possible haplotypes, only four were found, which suggests that these four polymorphic sites are in strong linkage disequilibrium. Analysis of the association of G6PD mutations with F8C/G6PD haplotype revealed that nt 517, 592, 835, and 1387 mutations are linked to haplotype VI+VII, whereas the nt 519 mutation is linked to haplotype III. The finding that some G6PD mutations are associated with a particular F8C/G6PD haplotype may be useful for future population studies.

Clinical presentations and predictive variables of thyroid microcarcinoma with distant metastasis

BACKGROUND

Thyroid microcarcinoma is not an uncommon disorder. The purpose of this study is to analyze the clinical presentation and predictive factors for patients with thyroid microcarcinomas who have distant metastases.

METHODS

We retrospectively reviewed and analyzed the clinical variables of 97 patients with thyroid microcarcinoma during the period from 1977 to 1995. The patients were divided into 2 groups representing patients with and without distant metastases. These data were analyzed by the Mann-Whitney U, chi 2 and Fisher's exact tests.

RESULTS

Of the 97 patients with thyroid microcarcinomas, there were 6 (6.2%) cases (F/M = 5/1) with distant metastases. Among them, 4 cases were papillary carcinomas and 2 cases were follicular carcinomas. The parameters: age at diagnosis (P = 0.0137), one month postoperative serum thyroglobulin (Tg) level (P = 0.0215), cervical lymph node metastasis (P = 0.0097), and follicular cell type (P = 0.0079), were determined to be factors predictive for distant metastases by statistical analysis. There were no statistical differences between gender (P = 0.5781), postoperative 131I uptake (P = 0.1238), tumor size (P = 0.0571), preoperative thyroid function (P = 0.4425), fine-needle aspiration cytology (FNAC) (P = 0.9723), preoperative thyroid scan (P = 0.9765), and operative methods (P = 0.1060) between these two groups.

CONCLUSIONS

Most thyroid microcarcinomas presented with relatively benign clinical courses, but patients with adverse predictive factors need more aggressive interventions to improve outcome.

Results of external beam radiotherapy in patients with well differentiated thyroid carcinoma

Surgical, thyroid hormone and radioactive 131I therapy are the standard curative treatments for well differentiated thyroid cancer. However, for residual, recurrent and nodal involvement of well differentiated thyroid cancer, external radiotherapy may be important in preventing distant metastases. The postoperative treatment of well differentiated human thyroid cancer with external radiotherapy is controversial. We retrospectively reviewed the records of 699 patients with papillary or follicular thyroid cancer, of whom 72 received external radiotherapy treatment after surgery. Thirty-two of these patients were at clinical stage 2 or 3 at the time of diagnosis while 172 patients at clinical stages 2 or 3 did not receive external radiotherapy after surgery. The patients who received external radiotherapy were older than those who did not (42.9 +/- 14.5 vs. 38.6 +/- 15.3), although this was not statistically significant. There were no significant differences in clinical parameters including surgical methods employed, histopathological types of cancer, follow-up stages, postoperative thyroglobulin levels, tumor size, accumulated 131I doses and survival rates between the two groups. To clarify the effect of external radiotherapy in patients with local invasion, we compared the survival rates of the patients with clinical stage 3 in the two groups and again no significant difference was found. During the follow-up period, 21 (28.4%) of the 72 patients who received external radiotherapy died of thyroid carcinoma. In our limited period of study, external radiotherapy did not improve the survival rate of patients with well differentiated thyroid cancer, though it appeared to cause temporary tumor regression.

The clinical significance of gall-bladder non-visualization in cholescintigraphy of patients with choledochal cysts

Intravenous radionuclide cholescintigraphy (IVRC) provides a very specific picture for choledochal cysts. However, the clinical significance of the non-visualization of the gall-bladder (GB) activity in these cases is unclear. In this study, we reviewed 27 patients with choledochal cysts who underwent IVRC within 7 days prior to operation and correlated the GB findings on IVRC with the histopathological results. In 18 of the 27 patients (66.7%), there was non-visualization of the GB at 4 h post injection. Among these, two had histopathological features of acute cholecystitis (AC), 11 had chronic cholecystitis (CC), and five had normal GBs. In the other nine patients with visualization of the GB, there were five cases of CC and four normal GBs. If we apply the finding of non-visualization of the GB at 4 h post injection as the criterion for the diagnosis of AC, the diagnostic accuracy was only 40.7% (11/27). We concluded that: (1) GB disease (AC and CC) was common (66.7%: 7.4% and 59.3% respectively) in choledochal cyst patients. (2) Non-visualization of the GB on IVRC did not necessarily indicate AC in choledochal cyst cases, and the diagnostic accuracy was low. (3) GB disease is not the only cause of GB non-visualization on IVRC. A huge choledochal cyst causing a mass or reservoir effect may be a cause of GB compression and result in non-visualization of the GB.

G6PD NanKang (517 T-->C; 173 Phe-->Leu): a new Chinese G6PD variant associated with neonatal jaundice

Using a non-radioactive PCR-SSCP technique, we identified a novel glucose-6-phosphate dehydrogenase (G6PD) mutation in a Chinese newborn with neonatal jaundice. This new variant (G6PD NanKang) causes a T to C change at nucleotide position 517, producing a Phe173Leu substitution in the human G6PD protein. Since the 517 mutation does not create or remove any known restriction site, we introduced an artificially created site by adding a primer containing a mismatched base to the PCR reaction mixture. The mismatched base accompanying the nearby 517 T-->C mutation generates an XhoI site which is suitable for distinguishing normal from mutant alleles. Using this approach, the 517 mutation can be diagnosed quickly at the DNA level.

Parathyroid carcinoma with postoperative prolonged hypocalcemia in a patient with chronic renal failure

Parathyroid carcinoma is a rare disease that usually presents with severe hypercalcemia and marked elevation of parathyroid hormone level. A 64-year-old male patient with repeated episodes of renal stones sustained chronic renal failure. Subsequently, he developed acute uremic symptoms and underwent a left upper parathyroidectomy. Parathyroid carcinoma was diagnosed after surgery. Asymptomatic hypocalcemia was the initial presentation. Protracted symptomatic hypocalcemia developed 8 months postoperatively, accompanied by an extremely high parathyroid hormone level. Delayed "bone hunger" syndrome concomitant with down-regulation of the parathyroid hormone receptors or production of parathyroid hormone with diminished bioactivity may have been the possible causes.