The role of surgery in the treatment of immune thrombocytopenic purpura (ITP) is still discussed. The aim of this study was to verify our criteria of patient selection for splenectomy, to analyze the results of a protocol for the evaluation of the hemorrhagic risk, and to discuss long-term results of 70 patients with ITP who underwent surgical treatment from 1984 to 1990. All patients received steroid therapy. Sixty-two patients were given high doses of IgG (600 mg/kg/iv bolus) pre-operatively in order to obviate the need for intra-operative platelet transfusions. Forty-three patients showed a significant increase in the platelet count, 8 a moderate increase, while 11 patients did not respond. No operative mortality was observed, however postoperative minor complications occurred in 14 (20%) patients. Accessory spleens were found in 11 (15.7%) patients. Mean follow-up was 21 months. Response to splenectomy was considered as complete (platelets greater than 150,000 mm3 with no need for medical treatment) in 63 (90%) patients. No response was observed in 7 patients. In 2 of the non-responders postoperative indium-111 scan revealed accessory spleens and ITP remitted after accessory splenectomy. All non-responders were in the group of patients who did not respond to the pre-operative infusion of high dose IgG. It can be concluded that splenectomy is a safe and effective treatment for ITP and that response to pre-operative infusion of IgG may be considered as predictive for the outcome after splenectomy.

Adolescent↗

PubMedDate not supplied

Pathogenetic aspects of organ-specific autoimmunity.

In the last few years a great deal of information on the etiopathogenetic aspects of organ-specific autoimmune diseases (OSADS) has been obtained. It has been shown that genetic factors play an etiologic fundamental role. They are responsible for the dysregulation of the immune system and for the target organ susceptibility which favour the onset of the diseases. Putative environmental factors, such as viral infections, can act as initiating or precipitating events only in genetically predisposed individuals. Immunological mechanisms capable of triggering autoimmune responses have been demonstrated. Data obtained from experimental models and from humans suggest that the ongoing expansion of autoreactive T cells with specificity for autoantigens (AAgs) can be considered as the main immunological event capable of inducing and maintaining the target organ damage. These cells can activate different effector systems, i.e., autoantibody (AAb)-producing B cells, cells with cytotoxic activity, etc., by releasing different combinations of lymphokines. In overt diseases AAbs are directly involved in the pathogenesis of lesions due to autoimmune responses against functional molecules and cellular receptors. The pathogenesis of the common inflammatory destructive lesions of the target organs is more complex and not yet clarified. A large proportion of T cells present in the inflammatory infiltrates are apparently not directed to the AAgs. Most cells display cytolytic activity and may contribute to tissue damage by releasing lymphokines which activate other cells and cascade the process. Vicious cycles, i.e., upregulation of class II and I molecules, alterations of the cytokine network, etc., are supposed to be involved in the maintenance of target organ lesions.

Autoantibodies↗

PubMedDate not supplied

Role of interleukin-4 in the induction of human IgE synthesis and its suppression by interferon-gamma.

Supernatants (SN) from 10 phytohemagglutinin (PHA)-stimulated human T cell clones (TCC), selected for their helper function on IgE synthesis, were found to provide IgE helper activity in atopic B cells showing low or undetectable spontaneous in vitro IgE synthesis. In contrast, SN from 5 PHA-stimulated TCC unable to provide helper function for IgE synthesis consistently failed to elicit IgE production. SN active on IgE synthesis contained high concentrations of interleukin-4 (IL-4), whereas inactive SN did not contain detectable amounts of IL-4. Moreover, the IgE helper activity of TCC SN was strongly inhibited by the addition of interferon-gamma (IFN-gamma) to B cell cultures. These data suggest that IL-4 may play a role in the induction of in vitro human IgE synthesis, whereas IFN-gamma displays an inhibitory effect.

B-Lymphocytes↗