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L Leenhardt

Publications and source records attributed to L Leenhardt.

At least 19 recordsLinked to original sources
PubMed2005

Effect of levothyroxine replacement therapy on coagulation and fibrinolysis in severe hypothyroidism.

OBJECTIVE: We previously demonstrated that patients suffering from moderate hypothyroidism were at increased risk of thrombosis contrasting with the bleeding tendency of those presenting severe hypothyroidism. The latter state is associated with hemostatic anomalies including von Willebrand type 1 disease and increased fibrinolytic capacity. With the exception of von Willebrand type 1 disease, reversibility of hemostatic changes is not established after levothyroxine replacement therapy. Therefore our objective was to analyze the reversibility of these anomalies. MATERIALS AND METHODS: We analyzed the impact of levothyroxine treatment on lipid parameters, fibrinogen, platelet count, D-dimers, alpha2 antiplasmin activity, plasminogen activity, tissue plasminogen activator antigen (t-PA Ag), plasminogen activator inhibitor type 1 antigen (PAI-1 Ag) and coagulation factors (factor VIII coagulant, von Willebrand factor antigen, von Willebrand factor and factor IX) in 23 patients with severe hypothyroidism (TSH level > 50 mU/ I). RESULTS: Mean fibrinogen levels increased by 14.2% while t-PA Ag and PAI-1 Ag increased by 42.6 and 69%, respectively, after correction of hypothyroidism. Interestingly, post-treatment PAI-1 Ag levels tended to be higher in patients with normal-high final TSH levels than in patients with normal-low final TSH levels. Our results suggest that normalization of fibrinolysis is obtained after a transient decrease of fibrinolytic activity. We also confirmed the correction of coagulation factor abnormalities upon levothyroxine replacement therapy. CONCLUSIONS: We demonstrated that the coagulation disorders and the hyperfibrinolytic status of severe hypothyroid patients were corrected upon levothyroxine therapy. However, the clinical consequences of the transient decrease of the fibrinolytic activity during the course of TSH normalization need further studies.

Adult↗
PubMed2005

Usefulness of fine needle aspiration cytology in the diagnosis of loco-regional recurrence of differentiated thyroid carcinoma.

AIM: The aim of our study was to define the usefulness of fine needle aspiration cytology (FNAC) in the assessment of loco-regional recurrence of differentiated thyroid carcinoma (DTC). METHODS: Among 1182 consecutive patients treated and followed for DTC from 1992 to 2001, we retrospectively analysed 65 FNAC results of patients presenting a suspicion of loco-regional recurrence. Recurrences were proved at histology in 35 cases and by cervical radioiodine uptake on post-therapeutic WBS (whole body scan) in nine cases. RESULTS: Among the 44 recurrences, FNAC results were malignant, benign and unsatisfactory in 33, two and nine cases, respectively. For the diagnosis of malignancy, FNAC sensitivity was 94%, specificity 100%, positive predictive value 100% and negative predictive value 87%. In the 35 cases where divergent results between diagnostic WBS (37-111MBq (131)I) and Tg level were observed, FNAC assessed the final status in 22 cases (malignant and benign in 17 and five cases, respectively). Of the 12 non-functioning and non-secreting lesions, FNAC diagnosed malignancy in four of the five malignant cases and ruled out malignancy in all seven benign lesions. CONCLUSION: These results outline the interest of FNAC in the assessment of loco-regional recurrences of DTC, especially when classical follow-up tools such as WBS and/or Tg level are unable to detect the recurrences.

Adult↗
PubMed2004

Relationship of circulating C-reactive protein levels to thyroid status and cardiovascular risk in hyperlipidemic euthyroid subjects: low free thyroxine is associated with elevated hsCRP.

The mechanism(s) by which low circulating levels of thyroid hormones may lead to development of premature atherosclerosis remain to be established. These mechanisms include indirect effects of thyroid hormones on cardiovascular risk factors such as plasma lipoproteins, homocysteine and fibrinogen. High-sensitivity C-reactive protein (hsCRP) has been identified as an independent predictor of cardiovascular events. We presently investigated the relationship between hsCRP and free thyroxine (FT4) levels in a large population of euthyroid hyperlipidemic patients (n=429, mean age: 47.1 years, 28% of current smokers). None of these subjects presented a recent history of infection or inflammatory disease and those taking drugs known to influence thyroid or hsCRP were excluded. Serum FT4 levels were measured by radioimmunoassay and CRP, by a high-sensitivity immunoassay. In the population of non-smokers, plasma FT4 levels were negatively and significantly correlated with those of hsCRP (r=-0.13, P=0.02). Significant correlations between FT4 levels and age (r=-0.16, P=0.003), glycemia (r=-0.14, P=0.01), and fibrinogen (r=-0.18, P=0.001) were equally observed. Upon division of the population on the basis of FT4 tertiles, the mean level of hsCRP was significantly higher in non-smoker patients with the lowest FT4 tertile as compared to those displaying the highest FT4 level (3.04mg/l versus 1.77mg/l, respectively, P<0.05). No correlation between FT4 levels and CRP was found in smokers.In conclusion, we demonstrate that hsC-reactive protein is significantly negatively correlated with free thyroxine levels in non-smoker hyperlipidemic patients, suggesting that low thyroxine levels in euthyroid hyperlipidemic subjects constitute a new biomarker of elevated cardiovascular risk.

Biomarkers↗
PubMed2004

Advances in diagnostic practices affect thyroid cancer incidence in France.

OBJECTIVE: To analyse trends in diagnostic practices of thyroid diseases and to relate them to the increase in thyroid cancer incidence in France over time. DESIGN: From 1980 to 2000, a French retrospective multicentric (three endocrinology and three nuclear medicine centres) study of thyroid diseases was conducted on 20 consecutive unselected patients' records, sampled every 5 years in each centre. METHODS: Characteristics of the population and diagnosis procedures (thyroid ultrasonography (US), radionuclide scan, cytology and hormonal measurements) were described over time. Changing trends in operated patients and in cancer prevalence were analysed as well as the impact of practices on cancer incidence. RESULTS: The study included 471 patients (82% female, mean age 46.7, range 9-84 years), referred for nodular thyroid diseases (66.7%) or thyroid dysfunctions (33.3%). A significant increase in US (3 to 84.8%) and cytological practices (4.5 to 23%), and a decrease (89.4 to 49.6%) in radionuclide scan procedures were observed over time. Although the proportion of patients undergoing surgery remained constant (24.8%), the prevalence of cancer increased among operated patients from 12.5 to 37% (P=0.006). In a Cox's proportional hazard model stratified on the clinical characteristics of patients, only the cytological practice, regardless of its results, was significantly associated with the occurrence of cancer: relative risk (RR)=4.4 (95% confidence interval (CI): 1.1-16; P=0.04). CONCLUSIONS: From 1980 to 2000, a major evolution in clinical practices has led to the increase in thyroid cancer reported in France. Such changes in medical, as well as in surgical and pathological, practices must be taken into account in incidence measurement.

Adolescent↗
PubMed2001

Amyloid goiter as the initial manifestation of systemic amyloidosis due to familial mediterranean fever with homozygous MEFV mutation.

We describe a case of amyloid goiter revealing a systemic amyloidosis secondary to familial Mediterranean fever (FMF) with homozygous MEFV mutation, and we review the literature. A 45-year-old euthyroid Sephardic man, known to suffer from FMF, developed a goiter with cold nodule, after which a subtotal thyroidectomy was performed. Histologic evaluation revealed diffuse AA amyloid deposition without any associated thyroid neoplasia. At that time, no other organ was found to be affected by amyloidosis. Colchicine and levothyroxine were prescribed. Eight years later, the patient presented with a rapidly growing neck enlargement. He reported that he had discontinued colchicine therapy 2 years earlier. The serum thyrotropin (TSH) and calcitonin levels were normal. Renal, digestive, and salivary gland biopsies confirmed the presence of systemic AA amyloidosis. Despite the reintroduction of colchicine, the onset of compressive symptoms led to the completion of the total thyroidectomy. The histopathology again demonstrated amyloid deposition, and excluded a malignant neoplasm. Nine cases of amyloid goiter associated with FMF have been reported in the literature; none of them had an amyloid goiter as the first manifestation of systemic amyloidosis. To our knowledge, this is the first case of FMF in which an amyloid goiter preceded the development of secondary systemic amyloidosis. The cessation of colchicine therapy may have played a role in local relapse and the secondary spread of amyloid deposits.

Amyloidosis↗
PubMed2001

Components of the fibrinolytic system are differently altered in moderate and severe hypothyroidism.

T(4) levels are determinant of several components of the fibrinolytic system. However, relationships between hypothyroidism and alteration of fibrinolytic capacity are not well established, and published data remain conflicting. As the impact of hypothyroidism on both degradation and synthesis of proteins may vary according to the severity of the disease, we measured fibrinolytic activity across varying states of hypothyroidism. We measured fibrinogen, D-dimers (DDI), alpha(2)-antiplasmin activity, tissue plasminogen activator antigen (t-PA Ag), plasminogen, plasminogen activator inhibitor antigen (PAI-1 Ag), and factor XII (FXII) of the coagulation. We prospectively included 76 middle-aged female subjects: 25 controls, 24 patients displaying moderate hypothyroidism (TSH, 10--50 mU/L), and 27 patients with severe hypothyroidism (TSH, >50 mU/L). Blood pressure, body mass index, smoking habits, total cholesterol as well as high and low density lipoprotein subfractions, triglyceride, fasting glycemia, and insulinemia were recorded. We found a different pattern of fibrinolytic abnormalities according to the severity of hypothyroidism. Compared with controls, patients with moderate hypothyroidism displayed a decreased fibrinolytic activity, as reflected by lower DDI levels, higher alpha(2)-antiplasmin activities, and higher levels of t-PA and PAI-1 Ag. In sharp contrast, patients with severe hypothyroidism exhibited higher DDI levels, lower alpha(2)-antiplasmin activities, and lower t-PA and PAI-1 Ag levels. These results were not accounted for by confounding factors such as age, smoking, and components of the insulin resistance syndrome. Free T(4) was significantly associated with fibrinogen, alpha(2)-antiplasmin, PAI-1 Ag, total cholesterol, and triglyceride and was negatively associated with DDI. The main hypotheses underlying the mechanisms by which thyroid status may affect the fibrinolytic system remain to be established. In conclusion, patients with moderate hypothyroidism, who were consistently shown to be at high risk for cardiovascular disease, have decreased fibrinolytic activity. Subjects with severe hypothyroidism have a tendency toward increased fibrinolytic activity, and these modifications may participate to the bleeding tendency observed in such patients.

Adult↗
PubMed2001

Survival and therapeutic modalities in patients with bone metastases of differentiated thyroid carcinomas.

Data for patients with bone metastases (BMs) of differentiated thyroid carcinoma (DTC) were retrospectively studied to identify factors associated with survival. We especially studied the impact of therapies. Among the 1977 patients followed for DTC in our department from 1958 to 1999, 109 (77 females and 32 males; age range, 20--87 yr) presented BMS: All patients except 1 underwent total thyroidectomy, followed by radioiodine therapy (> or =3.7 gigabecquerels) in 95 cases. Survival rates at 5 and 10 yr were 41% and 15%, respectively. Univariate analyses indicated that a young age at BM discovery (P < 0.005) and the discovery of BM as a revealing symptom of DTC (P < 0.05) were features significantly associated with improved survival as well as radioiodine therapy (P < 10(-4)) and BM complete surgery (P < 0.02). Using multivariate analysis, the detection of BMs as a revealing symptom of thyroid carcinoma (P < 0.0005), the absence of metastasis appearance in other organs than bones during the follow-up (P < 0.03), the cumulative dose of radioiodine therapy (P < 0.0001), and complete BM surgery in young patients (P < 0.04) appeared as independent prognostic features associated with an improved survival.

Adult↗
PubMed2000

[Thyroid cancer in patients with hyperthyroidism].

OBJECTIVE: The prevalence of thyroid carcinoma in hyperthyroidism remains controversial. The aim of this retrospective study was to evaluate prevalence. PATIENTS AND METHODS: The prevalence of thyroid carcinoma was studied in 861 patients operated for clinical or infraclinical hyperthyroidism between 1992 and 1999. One hundred and fifty patients had a hot nodule, 13 of them with an associated goiter. Four hundred five patients had Graves' disease and 306 had a multinodular goiter. Multiple sections were made in all surgical specimens for pathology study. RESULTS: Prevalence in solitary nodules was 1.45%. For Graves' disease patients, it was 4.1%. Prevalence among patients with multinodular goiter was 4.9%. Among the cancers, 83% were microcarcinoma. Parathyroid morbidity after subtotal and total thyroidectomy was 0.56% and recurrent hyperthyroidism occurred in 1.6%. CONCLUSIONS: These findings are grossly identical to those observed in simple, nontoxic diffuse multinodular goiter. It would therefore be difficult to incriminate hyperthyroidism as playing a causal role in the development of thyroid cancer. These results do however provide an argument favoring total or near total thyroidectomy when surgery is performed in patients with hyperthyroidism.

Adult↗
PubMed2000

Post-Chernobyl thyroid carcinoma in children.

The dramatic increase in childhood thyroid carcinoma observed in Belarus and Ukraine as early as 4 years after the Chernobyl nuclear accident, is well recognized as being a consequence of exposure to radioactive iodine fallout. Uncertainties persist concerning the contamination and the dosimetric data. Thyroid nodule, cervical lymph nodes or systematic ultrasound thyroid screening in exposed children led to the diagnosis. The carcinomas affected younger subjects, were less influenced by gender, and were more aggressive at clinical and histological presentation than in the case with naturally occurring carcinoma. Total thyroidectomy and radioiodine treatment remain the treatment of choice. The prognosis is good but further studies are needed to evaluate the prognosis of children presenting with pulmonary metastasis. The project of the Newly Independent States Chernobyl Tissue Bank will facilitate molecular genetic research into this important public health issue. Nevertheless, clinicians must keep in mind the simplicity and the effectiveness of iodine prophylaxis.

Adolescent↗
PubMed1999

Indications and limits of ultrasound-guided cytology in the management of nonpalpable thyroid nodules.

Although ultrasound (US)-guided fine needle aspiration biopsy (FNAB) is widely prescribed in nonpalpable thyroid nodules, the goal of this study was to define precisely the indications and limits of US-FNAB in a series of 450 nonpalpable nodules. Among 94 surgically controlled cases, 20 (8 infracentimetric and 12 centimetric or supracentimetric) carcinomas were diagnosed. The diagnosis of malignancy was successfully made by US-FNAB in 16 of 20 carcinomas, 3 were missed because of insufficient cytological material, and 1 was misdiagnosed. US-FNAB sensitivity and specificity were 94% and 63%, respectively. A logistic model indicated that nodule size (P < 0.6) was not associated with histological diagnosis, but that solid hypoechoic features were more likely to be malignant (P < 0.0003), with US sensitivity and specificity for malignancy of 80% and 70%, respectively. Logistic regression indicated that adequate cytological material significantly increased with nodule size (P < 0.0001). This result outlined the limits of US-FNAB in small nodules. Hence, indication of US-FNAB appears judicious in centimetric or supracentimetric nodules or in solid and hypoechoic ones. Such a management would allow the discovery of 15 of 20 carcinomas and would avoid 16% of unnecessary biopsies.

Adolescent↗
PubMed1999

[What is the contribution of imaging?].

Thyroid imaging has an essentially diagnostic value, but is also plays a role in definition of indications and operative techniques. Ultrasound is the most useful examination. Scintigraphy has become less useful, but remains indicated in hyperthyroidism and in certain retrosternal goitres inaccessible to ultrasound. The other examinations only have a limited value.

Humans↗
PubMed1999

Secondary thyroidectomy in patients with prior thyroid surgery for benign disease: a study of 203 cases.

BACKGROUND: The goal of this study was to evaluate the complication rate of secondary thyroidectomy in patients with prior thyroid surgery for benign disease. METHODS: Over an 8-year period, 203 thyroid reoperations were performed on 202 patients. All information relating to operative procedures, pathology, and complications was recorded prospectively. RESULTS: There were 24 men and 178 women with a mean age of 52 years. Prior surgery was unilateral in 136 cases (67%) and bilateral in 67 cases (33%), and 14 patients (6.9%) had more than 1 previous thyroid operation. For euthyroid or pretoxic recurrent nodular goiter, 190 reoperations were performed and 13 reoperations were performed for recurrent thyrotoxicosis. Twenty-three cancers were found in a specimen (11.4%). Completion thyroidectomy was done in 143 patients. Postoperative complications occurred in 21 patients (10.4%): recurrent laryngeal nerve palsy (7 patients), hypocalcemia (8 patients), hematoma requiring surgical evacuation (5 patients), and wound infection (1 patient). Complications remained permanent in 4 patients (2%). CONCLUSIONS: The permanent complication rate is higher in thyroid reoperations than in primary thyroid operations. However, we believe that this 2% rate is low enough to allow reoperation whenever it is necessary, provided precise operative rules are respected.

Adult↗
PubMed1998

[Management of 29 children with thyroid cancer following the Chernobyl accident].

As a consequence of the Chernobyl nuclear power plant accident, a considerable increase of thyroid cancer among contaminated children has been reported in Ukraine, Belarus and Russia. A group of 29 children aged from 5 months to 10 years (mean 4.7 years) at the time of the accident, with a papillary thyroid cancer, have been examined at the Pitié-Salpêtrière hospital in Paris. The cancer was discovered by systematic ultrasonography in only 25% of cases. No reliable dosimetric estimation was achieved. The initial surgical treatment was performed in Ukraine. Cervical lymph node and pulmonary metastases were present in 24 and 11 cases respectively. A complementary surgical treatment was necessary for 9 children and one to four radioiodine treatments were given to 24 children. With a mean delay of 7 years after the cancer discovery, an apparent cure or a remission was obtained for 20 children, 6 children have cervical lymph node metastases requiring a surgical treatment and 3 have evolving lung metastases. The management of the great number of foreseeable cases of thyroid cancer requires an improved systematic screening, a large number of rooms dedicated to high activity radioiodine treatments, funds for disposable material and training missions.

Child↗
PubMed1997

[Repeated thyroid surgery. Indications and results].

OBJECTIVES: To analyze the histology results and to assess operative risk of iterative operations for thyroid surgery. PATIENTS AND METHODS: A total of 249 re-operations were performed in 248 patients over a 6.5 year period. Two groups of patients were defined according to the indications for re-operation. Group 1: 80 patients; pathology examination of the surgical specimen discovered thyroid cancer. Group 2: 169 patients; recurrent nodular goitre after an initially benign disease. RESULTS: In group 1, 14 cancers were bilateral (17.5%) and 7 patients had cervical node metastases (8.8%). In group 2, 19 cancers were discovered (11.1%), including 5 cases with cervical node invasion (26.3%) and 4 with visceral metastases (21.1%). Twenty complications occurred in 20 patients (8%): compressive cervical hematomas (n = 3, 1.2%), recurrent nerve palsy (n = 7, 2.8%), hypoparathyroidism (n = 9, 3.6%; including 3 definitive cases, 1.2%) and mediastinitis (n = 1). These complications were significantly more frequent in patients re-operated for hyperthyroidism or those who had a past history of more than one cervicotomy. CONCLUSION: The frequency of bilateral cancer justifies completing thyroidectomy after partial thyroidectomy. The rate of definitive complications after re-operations is greater than first line cervicotomy but is low enough to allow iterative surgery using rigorous procedure in selected patients.

Goiter, Nodular↗
PubMed1997

[Management of microcancer].

Most of the papillary thyroid microcarcinomas have an excellent prognosis, though some of them, like macrocarcinomas, lead to local recurrences or distant metastasis. Detection of high risk factors to choose between conservative or aggressive treatment would be essential but is difficult and controversial, criterias being multiple. This is why we favour in most instances total or near total thyroidectomy with nodal dissection, morbidity of this surgery being very low. TSH suppression treatment is routinely advocated but not adjunctive radioiodine ablation. This approach authorizes an easier long term follow up.

Carcinoma, Papillary↗
PubMed1996

[Thyroid microcancer].

The prevalence of papilliary thyroid microcarcinomas is very high. A great majority has an excellent prognosis. However some of them lead to local recurrences or distant metastasis. Therefore it should be important do detect high risk factors to choose between conservative or aggressive treatment. However this proves to be difficult and it seems reasonable to perform in most instances a total or near total thyroidectomy with nodal disection. TSH suppression treatment is routinely advocated but not adjunctive radioiodine ablation. This approach authorizes an easier long term follow up.

Carcinoma, Papillary↗