Hemodynamic changes after levothyroxine treatment in subclinical hypothyroidism

In hypothyroidism, lack of thyroid hormones results in reduced cardiac function (cardiac output [CO]), and an increase of systemic vascular resistance (SVR). We speculated whether hemodynamic regulation in subjects with subclinical hypothyroidism (SH) (defined as mildly elevated thyrotropin [TSH] despite free thyroxine [T(4)] and triiodothyronine [T(3)] estimates within reference range) would benefit from levothyroxine (LT(4)) substitution. CO was measured by impedance cardiography, which is an observer independent method with high precision, and mean arterial pressure (MAP) by oscillometry. SVR was then calculated as MAP/CO. Measurements were performed before and after 60 degrees head-up tilting, and before and after LT(4) substitution. Plasma levels of catecholamines were also measured. In 16 otherwise healthy women with SH (ages 44-74 years; serum TSH in mean 17.1 mU/L (range, 6.8-27), and normal free T(4) and T(3) estimates) LT(4) treatment resulted in 6% reduction in supine MAP (p < 0.01), 14% increase in upright CO (p < 0.05), and 13%-20% decrease in SVR (supine and upright position, respectively) (p < 0.05). Plasma norepinephrine as well as epinephrine decreased during LT(4) treatment (p < 0.05). These changes were qualitatively similar but quantitatively less pronounced than in 15 women with overt hypothyroidism, also studied. Taking the two groups together (n = 31), pretreatment thyroid function (expressed as either TSH or free T(4) estimate) correlated to CO and SVR as well as the changes induced by LT(4) (p < 0.05), i.e., the lower the thyroid function the lower the CO and the higher the SVR, and the greater the response to LT(4). We conclude, that LT(4) treatment in SH results in changes in hemodynamic parameters of potentially beneficial character. SH and overt hypothyroidism should be regarded as a continuum, and our data favor earlier and more aggressive treatment of SH.

Haemodynamic changes following treatment of subclinical and overt hyperthyroidism

OBJECTIVE

Hyperthyroidism has profound effects on the cardiovascular system, including reduced systemic vascular resistance (SVR) due to relaxation of vascular smooth muscle cells, enhanced heart rate (HR) and cardiac output (CO) due to an increase in cardiac diastolic relaxation, contractility and heart rate. Subclinical hyperthyroidism is characterised by reduced serum TSH levels despite free thyroxine (T4) and tri-iodothyronine (T3) estimates within the reference range, in subjects with no obvious symptoms of hyperthyroidism. We measured haemodynamic changes (using impedance cardiography) in subjects with endogenous subclinical hyperthyroidism in order to elucidate whether these patients had signs of excess thyroid hormone at the tissue level.

DESIGN

The patients were otherwise healthy women with a multinodular goitre (n=6; age 47-81 years; serum TSH 0.006-0.090 mU/l and normal free T4 and T3 estimates), studied before and after normalisation of TSH (0.280-1.120 mU/l) by means of radioiodine treatment, and they were compared with 9 overt hyperthyroid patients (2 with multinodular goitre and 7 with Graves' disease) in the untreated state and after euthyroidism had been obtained.

RESULTS

Treatment of the subclinical hyperthyroid women resulted in 11% reduction in HR (P<0.02), 19% reduction in CO from (means+/-s.d.) 6.93+/-2.15 l/min to 5.58+/-1.94 l/min (P<0.05), and 30% increase in SVR (P<0.02). Similar but more pronounced changes were seen in the hyperthyroid group: 17% reduction in HR, 25% reduction in CO and 46% increase in SVR (all at least P<0.05). Taking all 15 patients together, thyroid function (as measured by free T3 index (FT3I) or TSH) correlated significantly to the haemodynamic parameters as follows: the higher the thyroid function the lower the mean arterial pressure and SVR, and the higher the CO and central aortic compliance (stroke volume/pulse pressure) (P<0.05). Plasma norepinephrine increased significantly after treatment of the overt hyperthyroid patients, whereas epinephrine did not change, and no changes were seen among subclinical hyperthyroid patients.

CONCLUSION

Treatment of endogenous subclinical hyperthyroidism resulted in significant changes in several haemodynamic parameters regarding the heart and the vascular system, compatible with some degree of excess tissue exposure to thyroid hormones in the untreated state. Our data favour more aggressive treatment of these patients, and endogenous subclinical hyperthyroidism might be regarded as a mild form of hyperthyroidism.

[Head circumference in relation to sonographic morphometry of the cerebral ventricles in neonates and infants]

AIM

To determine normal values of sonographic measurements of the brain in neonates and infants.

METHOD

Cerebral ultrasonographic examinations were performed in 143 healthy newborns and infants. The size of the ventricles was determined by ascertaining distances as well as performing planimetric measurements of the ventricular area and circumference in standardized planes.

RESULTS

Throughout the course of the study we observed a continous increase in size and a strong correlation with head circumference. The middle coronary plane used for the measurements allows the accurate representation of the ventricles and a more objective assessment of size.

CONCLUSION

Based on the morphometric data, charts for the determination of ventricular size were developed.

[EEG findings in patients with systemic lupus erythematosus]

We have examined electroencephalography (EEG) and Mini-Mental State Examination (MMSE) in 38 patients with verified diagnosis of systemic lupus erythematosus (SLE). In the clinical neurological finding there were epileptic attacks in 9 patients, 10 patients suffered from stroke, 15 patients from lupus headache, 4 patients from psychosis, in 15 patients cranial neuropathy was present, in one person extrapyramidal syndrome. EEG findings were in 12 patients normal (32%), in 26 patients abnormal (66%). In 3 cases there were focal abnormalities (8%), in 19 cases episodic ones (48%), four times abnormalities were diffuse (10%). Diffuse abnormalities correlated in EEG findings with case history of GM attacks.

The influence of traumatic brain lesion on sleep architecture

The authors deal with sleep changes in patients after brain injury. Ten patients were examined with the use of daytime routine EEG and night polysomnography. The amount of REM sleep is most sensitive to brain damage and is reduced in all patients with nonspecific epileptiform changes in the EEG. Changes in deep synchronous sleep are less frequent and are not in correlation with the prevalence of epileptiform changes. Thus the reduction of REM sleep seems to be a sensitive marker of development of epileptiform EEG-changes and perhaps could play a predictive role of development of post-traumatic epilepsy.

EEG spectrum as information carrier

Spontaneous and provoked changes of vigilance and consciousness are determined by TCS (thalamocortical system) activity. This is relatively easy to monitor using EEG, which is a complex curve but open to analysis, e.g., by means of FFT (fast Fourier transformation). Twenty six persons (six normal controls, twelve epileptics, eight dements) had EEG recorded during rest, reaction to sound, and perception to simple tones or chords from Smetana's symphonic poem Vysehrad. The length of reaction time was found dependent on FFT changes: the longer the time, the higher are the delta and the lower the alpha activities in the EEG spectrum. However, with alpha increasing during relaxation, the reaction time grew longer regardless of whether delta had increased due to hyperventilation, sleep or subclinical epileptic discharges. During the perception of tones, FFT showed changes in the alpha and delta bands different from those during the perception of chords, and different again during relaxation, and that in both normal controls and epileptics. The demented persons revealed no discernible FFT differences in the perception of either tones or chords, the only differences were found in the resting sections of the spectrum. One and the same stimulus produced a stereotype FFT response, i.e., different stimuli elicited different FFT response in healthy and epileptic persons. The dements responded to identical stimuli differently, and had stereotype FFT response elicited by the same stimuli. The results suggest that FFT can represent the information content of the EEG curve and, indirectly, also that of micro-EEG as it reverberates between the thalamus and the cortex in the form of neuronal activity impulsations. This interneuronal impulsation coding is disordered in dements with atrophy of the cortex; it is marked, on the one hand, by increased variability in the perception of identical stimuli, and, on the other hand, by impaired differentiation, and, consequently, by increasingly stereotype responses to different stimuli.

Serum levels of the cytokines IL-1beta, IL-6 and ICAM-1 after 131I-treatment of Graves' disease and nodular goiter

Cytokines might be involved in the immunological flare up, seen in some patients after 131I-treatment. Therefore, we measured serum levels of interleukin-6 (IL-6), interleukin-1beta (IL-1beta), interleukin-6 soluble receptor (IL-6sR) and Intercellular-adhesion-molecule-1 (ICAM-1) as well as tumor necrosis factor (TNF-alpha) after 131I-treatment of Graves' disease and nodular goiter. Seven patients with Graves' disease, eight with toxic nodular goiter and seven with non-toxic nodular goiter, were followed after 131I-treatment. The patients were treated in the euthyroid state. Blood samples were drawn at day 0, 4, 7, 21 and after 3 months. Significant increases were seen in free T4 index (FT4I), free T3 index (FT3I) and thyroglobulin (Tg) within the first weeks, and TSH simultaneously decreased. None of the cytokines demonstrated any change during follow-up, neither in the entire group nor in subgroups. FT4I and FT3I correlated significantly to ICAM-1. In conclusion, our data suggest that there does not seem to be prolonged cytokine activation after 131I-treatment for thyroid disorders.

Tying twin brackets

To achieve orthodontic tooth movement, archwires must be tied to the bracket slots. Metal or elastic ligatures are used for this purpose, and the way they are tied affects tooth movement. Because of their design, twin brackets can be tied in a large variety of ways. Knowing how to use all the bracket's resources makes for better and faster treatment results.

[Radioiodine therapy of benign thyroid disease in Denmark]

The aim of the study was to evaluate differences in the use of radioactive iodine in the treatment of benign thyroid disease in Denmark. A questionnaire was distributed to all departments in Denmark which administer radioiodine in the treatment of benign thyroid disease (n = 20). Radioiodine is used for patients with toxic nodular goitre and for patients with relapse of toxic diffuse goitre. Four departments did not use radioiodine for volume reduction in non-toxic goitre. Patient informations included very different recommendations regarding cautions in relation to radioiodine treatment. Radioiodine is widely used in the treatment of benign thyroid disease. We recommend a national standardization of the cautions in relation to radioiodine treatment.

Terminal deoxynucleotidyl transferase-negative acute lymphoblastic leukemia

OBJECTIVE

Terminal deoxynucleotidyl transferase (TdT) is a useful marker in the diagnosis of acute lymphoblastic leukemia (ALL) (French-American-British [FAB] L1 and L2) and is most useful in distinguishing ALL from mature B-lymphoid neoplasms, such as Burkitt lymphoma (FAB L3) and other lymphoid malignancies. The frequency of TdT-negative ALL is not known. Here we report 3 TdT-negative ALL cases that met the criteria for T-cell ALL.

DESIGN

We reviewed approximately 200 cases of ALL retrieved from the database at our institution. All cases were evaluated using Wright-Giemsa, myeloperoxidase, butyrate, and TdT staining; immunophenotyped using flow cytometry; and studied using Southern blot analyses for T-cell receptors and immunoglobulin gene rearrangement.

RESULTS

All ALL cases (L1 and L2) were TdT-positive, except for 3 cases that were of early T-cell lineage. None of the 3 cases demonstrated positivity for TdT in immunofluorescence staining with polyclonal antibodies or flow cytometry with monoclonal antibodies. Flow cytometric analysis confirmed a pre-T-cell immunophenotype in all 3 cases. One of the cases showed rearrangement of a T-cell antigen receptor and immunoglobulin heavy chain (J(H)). A second case showed germline configuration of T-cell receptors, but also showed rearrangement of the J(H), despite the expression of T-cell markers only.

Shwachman-Diamond syndrome: early bone marrow transplantation in a high risk patient and new clues to pathogenesis

Shwachman-Diamond syndrome (SDS) is an autosomal recessive disorder characterised by exocrine pancreas insufficiency, metaphyseal dysostosis and bone marrow dysfunction. Recurrent severe bacterial infections and susceptibility to leukaemia are the major causes of morbidity and mortality occurring preferentially in patients with pancytopenia and features of myelodysplasia. Here we report a patient with SDS leading to recurrent bacterial infections and a deteriorating condition since early infancy. Extensive investigations disclosed severe pancytopenia, myelodysplasia and a clonal cytogenetic abnormality, inv(14)(q11q32), as risk factors of leukaemic transformation. He therefore underwent allogeneic geno-identical bone marrow transplantation which resulted in correction of all haematological and immunological abnormalities within an 18-month follow up period. Conclusion Bone marrow transplantation may be considered early as a valuable treatment option especially in high risk Schwachman-Diamond syndrome patients anticipating malignant transformation, life-threatening severe infections or further organ damage.

De novo CD5+ Burkitt lymphoma/leukemia

CD5 is a T-cell marker aberrantly expressed in B-cell chronic lymphocytic leukemia and mantle cell lymphoma. Other B-cell neoplasms, including Burkitt lymphoma, are usually CD5-. We report 4 cases of de novo CD5+ Burkitt lymphoma/leukemia in elderly patients, all of whom were in a leukemic phase and had variable lymph node and splenic involvement. The blasts were typically medium sized, with folded nuclei, distinct but not prominent nucleoli, and moderate amounts of somewhat vacuolated basophilic cytoplasm; they were terminal deoxynucleotidyl transferase--negative and surface immunoglobulin--positive. All 4 cases demonstrated c-myc rearrangement, but none had t(14;18), t(11;14), or cyclin D1 overexpression or rearrangement. Only 1 patient achieved complete remission after hyper-CVAD (hyperfractionated cyclophosphamide, vincristine, doxorubicin, dexamethasone) therapy. One patient responded poorly to hyper-CVAD, and 2 patients died during induction chemotherapy. These rare cases of aggressive lymphoid malignancy with CD5 positivity and molecular features associated with Burkitt lymphoma/leukemia are best classified as Burkitt leukemia. However, the morphologic and immunophenotypic similarity to the blastoid variant of mantle cell lymphoma are diagnostically challenging. The diseases can be distinguished at the genetic level, since Burkitt lymphoma involves the rearrangement of c-myc, and mantle cell lymphoma usually the overexpression or rearrangement of cyclin D1.

Serum levels of advanced glycation end products are associated with left ventricular diastolic function in patients with type 1 diabetes

OBJECTIVE

Impairment of left ventricular diastolic function, possibly caused by increased collagen cross-linking of the cardiac muscle, is common in patients with type 1 diabetes even without coronary artery disease. Advanced glycation end products (AGEs) cross-link tissue collagen and are found within myocardial fibers. The aim of this study was to examine for a possible association between circulating AGEs and left ventricular cardiac function.

RESEARCH DESIGN AND METHODS

Left ventricular diastolic and systolic function were assessed by M-mode and Doppler echocardiography in 52 patients with type 1 diabetes, age 40 +/- 13 (mean +/- SD) years, diabetes duration 17 +/- 13 years, and HbA1c 8.3 +/- 1.1%. Serum levels of AGEs and N epsilon-(carboxymethyl)lysine (CML) were measured by newly developed competitive immunoassays.

RESULTS

A positive correlation was found between serum levels of AGEs and isovolumetric relaxation time (IVRT), r = 0.46 (P < 0.0008), and left ventricular diameter during diastole, r = 0.37 (P < 0.008). The systolic parameters did not correlate with serum levels of AGEs. Stepwise regression analysis showed that 21% of the IVRT variation could be explained by serum levels of AGEs (F = 11.4, P < 0.002), whereas serum levels of CML, HbA1c, albumin excretion rate, diabetes duration, and mean arterial blood pressure were of no importance. AGE levels were significantly increased in men compared with women (P < 0.03) and present or former smokers (P < 0.04).

CONCLUSIONS

Increased serum levels of AGEs, unlike serum levels of CML, are associated with heart stiffness in patients with type 1 diabetes, possibly mediated by the cross-linking properties of AGEs.

Transition of nodular toxic goiter to autoimmune hyperthyroidism triggered by 131I therapy

The use of 131I treatment in nodular toxic goiter is widely accepted. In this article, we describe transition of nodular toxic goiter into an autoimmune toxic goiter with development of thyrotropin receptor antibodies (TRAb) as a side effect of 131I treatment. In this retrospective study, 149 patients with nodular toxic goiter (100 with multinodular goiter, 49 with a solitary autonomously functioning toxic nodule) were studied. Of these 149 patients 100 became permanently euthryoid after 1 dose of 131I, and due to persistent hyperthyroidism, 32 patients needed 2-5 doses to became euthyroid. After becoming euthyroid, none of these 132 patients had relapse of hyperthyroidism in the follow-up period. Based on evaluation of the thyroid hormone variables, 17 of 149 patients had a distinctly different pattern in the changes in thyroid hormones. They developed an increase in FT4I 3-6 months posttreatment after an initial fall in FT4I. Twelve of these 17 patients were treated with antithyroid drugs before the initial 131I dose. On samples of frozen sera (-20 degrees C) anti-thyroid peroxidase (TPO) and TRAb were followed for 6 months after 131I treatment in these 17 patients. A similar follow-up was done in 20 patients (10 with and 10 without antithyroid drug pretreatment), randomly selected from the patients who did not relapse. In the remaining 112 patients, anti-TPO and TRAb levels were measured only before the 131I treatment. Of the 17 patients with relapse, 6 developed TRAb concomitant with recurrence of hyperthyroidism (4% of the study group). In 5 of the 17 patients TRAb values remained absent throughout the follow-up period. The remaining 6 patients had elevated TRAb values before 131I treatment. Among the 132 patients who did not relapse, an additional 7 cases with presence of TRAb were found. A total of 9% of the study group was found to have TRAb before 131I pretreatment. Anti-TPO was found in 20 of 149 patients (13%) before 131I treatment. Complications, either hypothyroidism or TRAb-associated hyperthyroidism, were seen in 8 of 20 patients (40%) with anti-TPO before 131I treatment, compared to 9 of 129 (7%) without (p<0.005). In conclusion, TRAb and a Graves' like hyperthyroidism can be triggered by 131I treatment in patients with nodular toxic goiter. The presence of anti-TPO seem to be a marker of an increased risk of development of TRAb-associated hyperthyroidism as well as hypothyroidism, but both side effects can be seen despite the absence of anti-TPO autoantibodies.