Undefined CD4 lymphocytopenia without clinical complications. A report of two cases.

A form of idiopathic CD4 lymphocytopenia (ICL) has been recently described. Its diagnostic criteria have been defined by the Centers for Disease Control (CDC), Atlanta. Associations of ICL with hepatitis C infection have been reported, while some ICL patients have presented abnormalities partly similar to those observed in common variable immunodeficiency (CVI). This paper illustrates the immunological pictures of two subjects with a CD4 deficiency confirmed in a series of peripheral blood lymphocyte subset determinations, but not associated with other cellular or humoral immunity abnormalities and accompanied by poorly significant clinical manifestations (no opportunistic infections). Patient one has been observed for a very long period. Her serological picture has been negative and she is free from hypergammaglobulinemia. HIV infection can thus be ruled out. Patient two has not required any specific treatment so far. The CDC's diagnostic criteria for ICL are not fully met in the two cases. Their pictures meet many, though not all of the CDC criteria for the diagnosis of ICL. It is to be hoped that a protracted follow-up will allow an assessment to be made of the natural history of the two cases.

[Components of complement in patients with immediate hypersensitivity]. / Il complemento in soggetti con ipersensibilità immediata.

BACKGROUND: This prospective study was undertaken to assess the differences between the levels of the main plasma components of complement in allergic subjects and in those with pseudoallergic clinical manifestations. METHODS: Plasma C3 and C4 were evaluated in a total of 256 subjects examined consecutively at the allergology outpatients clinic of the Internal Medicine Division B, University of Turin. Total IgE and C1-inhibitor levels were also determined in 128 and 44 subjects respectively. RESULTS: C3 and C4 levels were not significantly different (p = 0.398 and p = 0.497) in 123 subjects with a positive and 133 with a negative prick test, nor in allergic subjects with respiratory as opposed to skin symptoms (p = 0.293 and p = 0.462), whereas the C-1 inhibitor was significantly lower (p = 0.046) in the respiratory subgroup. Total IgE was positively correlated with the C3 level (p = 0.036) in 75 allergic subjects. CONCLUSIONS: These findings suggest that plasma C3 and C4 values are not sufficient to discriminate IgE inflammation (positive prick test) and pseudoallergy (negative prick test) in the assessment of subjects with clinically suspected allergy. The positive correlation between IgE synthesis and C3 also points to an interaction between IgE synthesis and C3 regulation proteins in patients with IgE mediated diseases. Further investigation of other acute phase proteins (C reactive protein, fibrinogen) and the cytokines regulating their synthesis (IL-6) in such patients will help to clarify this correlation.

[CD4 lymphocytopenia in patients without significant clinical pathology]. / Linfocitopenia CD4 in pazienti senza significativa patologia clinica.

There are different causes of CD4 lymphocytopenia: neoplastic pathology, immunosuppressive therapy or other iatrogenic forms. In addition to these causes, an important role is certainly played by HIV infection which, at the AIDS stage, constantly accompanies progressive CD4 lymphocytopenia, with or without affecting the other lymphocyte components. CD4 lymphocyte deficits not correlated to HIV infection are relatively rare and are not always accompanied by progressive clinical manifestations of immunodeficiency. In the recent past an idiopathic form of CD4 lymphocytopenia (ICL) was recognised whose diagnostic criteria were defined by the Center for Disease Control (CDC) in Atlanta. Cases of ICL association with hepatitis C virus infection have been reported and anomalies partially shared by subjects suffering from common variable hypogammaglobulinemia (CVH) have been reported in some ICL carriers. The CD4 deficit in these patients is not associated with other cellular and/or humoral immunological anomalies and the clinical manifestations, essentially of scant importance, have not shown signs of progression towards severe immunodeficiency syndromes. The authors report 4 subjects with major CD4 deficit whose clinical characteristics do not match idiopathic lymphocytopenia and specific serological tests have excluded HIV infection. No known causes of CD4 lymphocytopenia have been found in these patients and they do not present major signs of clinical damage.

[Diagnosis of drug allergy. Role of specific IgE and IgG determination]. / Diagnosi di allergia ai farmaci. Ruolo del dosaggio di IgE e IgG specifiche.

In the diagnosis of drug allergies, the anamnesis and, in some cases, prick tests are without doubt indispensable approaches but they are not always able to provide optimal prognostic levels. Moreover, prick tests are sometimes contraindicated owing to their potential danger. This study evaluated the diagnostic efficacy of a test in vitro--the assay of IgE- and IgG-specific (RAST)--for a group of 16 drugs in 88 patients referred for allergological consultancy after clinical manifestations attributable to the administration of a drug (30/88 cases) or more than one drug (58/88). Disorders had appeared at least one week after the start of drug treatment, an interval that is compatible with the development of an immune response. In 17/88 (19.3%) patients the in vitro test confirmed the presence of IGe and/or IgG against at least one of the drugs suspected in the anamnesis. In this series it was also found that there was a higher incidence of ADR in females (60/88) compared to males (28/88). Reactions to several drugs were more frequent than reactions to a single drug (58 cases vs 30). The association of ADR and the presence of other allergies in a particular individual was relatively rare (13/88 = 14.7%). These results confirm the value of RAST as a useful aid to improve the overall diagnosis of drug allergies and to make it safer.