Current perspectives on immunology and psychiatry

Peripheral thyroid dysfunction in depression

The involvement of the thyroid gland and thyroid hormones is generally believed to be important in the aetiopathogenesis of major depression. Major support comes from studies in which alterations in components of the hypothalamic-pituitary-thyroid (HPT) axis have been documented in patients with primary depression. However, screening thyroid tests are often routine and add little to the diagnostic evaluation. Overt thyroid disease is rare among depressed inpatients. The finding that depression often co-exists with autoimmune subclinical thyroiditis suggests that depression may cause alterations in the immune system, or that in fact it could be an autoimmune disorder itself. The outcome of treatment and the course of depression may be related to thyroid status as well. Augmentation of antidepressant therapy with the co-administration of thyroid hormones (mainly T3) is a well-documented treatment option for refractory depressed patients. Review of the literature suggests that there are no conclusive data on the role of thyroid function in depression. It is clear that depression is not characterised by an overt thyroid dysfunction, but it is also clear that a subgroup of depressed patients may manifest subtle thyroid abnormalities, or an activation of an autoimmune process. There is a strong possibility that the presence of a subtle thyroid dysfunction is a negative prognostic factor for depression and may demand specific therapeutic intervention.

Thyroid function in clinical subtypes of major depression: an exploratory study

BACKGROUND

Unipolar depression might be characterized by a 'low-thyroid function syndrome'. To our knowledge, this is the first study which explores the possible relationship of DSM-IV depressive subtypes and the medium term outcome, with thyroid function.

MATERIAL

Thirty major depressive patients (DSM-IV) aged 21-60 years and 60 control subjects were included. Clinical Diagnosis: The SCAN v 2.0 and the IPDE were used. The psychometric Assessment included HDRS the HAS and the GAF scales. Free-T3, Free-T4, TSH, Thyroid Binding Inhibitory Immunoglobulins (TBII), Thyroglobulin antibodies (TA) and Thyroid Microsomal Antibodies (TMA) were measured in the serum. The Statistical analysis included 1 and 2-way MANCOVA, discriminant function analysis and Pearson Product Moment Correlation Coefficient.

RESULTS

All depressive subtypes had significantly higher TBII levels in comparison to controls. Atypical patients had significantly higher TMA in comparison to controls. No significant correlation was observed between the HDRS, HAS and GAF scales and thyroid indices. Discriminant function analysis produced functions based on thyroid indices, which could moderately discriminate between diagnostic groups, but could predict good response to treatment with 89.47% chance of success.

CONCLUSION

Although overt thyroid dysfunction is not common in depression, there is evidence suggesting the presence of an autoimmune process affecting the thyroid gland in depressive patients

Can elective lymph node dissection decrease the frequency and mortality rate of late melanoma recurrences?

BACKGROUND

Although more than 90% of the morbidity and mortality from localized cutaneous melanoma occurs in the first decade after initial surgical treatment, melanoma can recur after a 10-year disease-free interval (DFI) with fatal consequences. We reviewed our melanoma data base of more than 8,500 prospectively acquired patients to identify clinicopathological factors that affect the type, rate of occurrence, and outcome of disease recurring 10 years or more after surgical treatment of primary cutaneous melanoma.

METHODS

From 1971 to 1997, 1907 melanoma patients treated at our cancer center reached or presented with a DFI of 10 years or more after surgical treatment of clinically localized melanoma. Of these, 217 (11%) patients had recurrences (mean DFI, 182 months). The sites of recurrence were local/in-transit in 26 (12%) patients, regional lymph nodes in 101 (47%) patients, and distant sites in 90 (41%) patients.

RESULTS

Univariate and multivariate analysis, using patient age and sex, type of initial treatment, and the site, Breslow thickness, and Clark level of the initial tumor, showed that the type of treatment for the primary tumor was a significant (P = .0005) prognostic factor in the development of late nodal recurrence. Of the 217 patients who had recurrences, 172 (79%) had undergone wide local excision for their primary melanoma, and 45 (21%) had undergone wide local excision plus elective lymph node dissection (ELND). The rates of nodal recurrence were 53% (92 of 172) and 20% (9 of 45), respectively, a significant (P = .0001) difference. When all patients with a DFI of 10 years or more were stratified by type of initial treatment, the ELND group demonstrated a significant improvement in disease-free survival and overall survival.

CONCLUSIONS

The risk of late-recurring nodal disease increases and the chance of long-term survival decreases when wide local excision is performed without ELND. With the advent of sentinel lymphadenectomy, ELND can be selectively performed only for those nodal basins with occult tumor cells, thereby decreasing operative morbidity but allowing identification and early removal of nodal micrometastases.

Viruses, neurosis and fatigue

The evidence for viral infections as a cause of anxiety, depression and fatigue is reviewed. It is argued that in order to fully understand any proposed relationship the effects of psychosocial factors on immunity, convalescence and illness behaviour must be acknowledged.

Urinary neopterin quantification indicates altered cell-mediated immunity in healthy subjects under psychological stress

In an effort to quantify changes in cell-mediated immunity (CMI) in healthy subjects under stress, we measured levels of neopterin, a well-validated marker of CMI activation, in the urine of medical students undergoing academic examinations. Neopterin/creatinine ratios measured on the first day of examinations (mean 46 mumol/mol) were significantly lower than those measured two weeks before (mean 78 mumol/mol, p = .004). Minimum neopterin production coincided with maximum subjective stress, as measured by a visual analogue scale. After examinations, neopterin/creatinine ratios rose (means 62 mumol/mol immediately after, and 65 mumol/mol two weeks after examinations), and these levels were not statistically different from those two weeks before examinations. Over this post-examination period, subjective distress was significantly lower than at either time point before examinations. We conclude that urinary neopterin/creatinine ratios may change significantly during periods of psychological stress, indicating concomitant alterations in CMI activation.

Natural killer cell function in adolescent and adult schizophrenic patients

The following study on natural immunology in schizophrenic patients aims at elucidating differential effects of psychopathological status and neuroleptic treatment. Natural killer (NK-) cell activity and antibody dependent cellular cytotoxity (ADCC) were tested in 24 adolescent schizophrenic patients and compared to 27 adult schizophrenics and healthy controls. Twelve adolescent patients were tested before and after 2 weeks on neuroleptic treatment. Age or psychopathological status did not have a significant impact on NK-activity or ADCC. There were no significant general effects resulting from neuroleptic treatment on NK-activity detectable in patients tested before and during treatment. However, there was a significant negative correlation between the differences of NK-activity (before and during treatment) and the NK-activity before treatment.

Neopterin measurement provides evidence of altered cell-mediated immunity in patients with depression, but not with schizophrenia

Neopterin is a validated marker of the activation of cell-mediated immunity in a variety of disease states. We measured neopterin and creatinine concentrations in the plasma and urine of 22 schizophrenic and 26 depressed patients admitted acutely to hospital, and compared results with those in a large group of normal controls. Neopterin/creatinine ratios were normal in the schizophrenic patients, but significantly elevated in the plasma of depressed patients. In each diagnostic group, the use of psychotropic drugs before admission had no effect on the neopterin ratios observed. Our findings indicate altered cell-mediated immunity in depression.

Neopterin production in acute schizophrenic patients: an indicator of alterations of cell-mediated immunity

This longitudinal study analyzed how the activation of cell-mediated immunity (CMI) was related to the severity of symptomatology in 25 acute schizophrenic inpatients (DSM-III-R, 295.31). Neopterin, which was used to monitor the activation of T-cells and macrophages, was found to be within the normal range, but the lowest neopterin concentrations were measured on day 0. By day 3, a significant increase of neopterin was observed. Compared with healthy controls, patients had significantly lower neopterin levels at baseline. The highest scores on the Clinical Global Impressions Scale and the Brief Psychiatric Rating Scale occurred on day 0 and decreased significantly over the observation period. In general, the increase of neopterin was accompanied by a decrease in psychopathological symptoms. These results' indicate that at study entry, when patients are acutely ill, activation of the CMI is reduced rather than increased. Possible pathophysiological mechanisms are discussed.