Hereditary angioedema type II--a study of two families.

Hereditary angioedema (HA) is caused by a quantitative or qualitative deficiency of C1 esterase inhibitor (C1 INH). We present a study of nine patients with HA belonging to two different families. The symptoms started before 10 years of age in most cases (78%). Facial edema (lips, eyes) and of the extremities (feet, hands) were the most frequent complaints. Three patients presented edema of the glottis and one of them underwent a tracheostomy twice. Laboratory tests, outside the acute crisis, revealed low levels of C4 in all patients. The serum levels of C1 INH were normal in seven patients; however, functional activity was not observed in any of them. After the use of a modified androgen (danazol), control of symptoms was observed in all patients, although functional activity was re-established in only five patients.

Magnetic resonance imaging in a patient with X-linked agammaglobulinemia and chronic meningoencephalitis.

The case of a boy with congenital agammaglobulinemia is reported. In spite of regular immunoglobulin replacement therapy (fresh plasma transfusion from family donors--20 ml/kg/month), he developed chronic meningoencephalitis (ME). Besides characteristic clinical signs of ME, he also presented at cerebrospinal fluid analysis pleocytosis with lymphocyte predominance and class II cytomorphology, and delta and theta waves in the EEG. Computerized tomography showed dilatation of the ventricles and marked cortical fissures (sulci). Magnetic resonance imaging showed a disease affecting white and gray matter. After diagnosis of ME, replacement therapy with Sandoglobulin (700 mg/kg every 2 weeks) was started. His condition gradually worsened, and coma and death occurred after a follow-up of 18 months. The etiological agent could not be identified.

A simple radial immunohemolysis assay for the measurement of functional complement C2 activity.

1. This study describes a simple radial immunohemolysis method for determining the hemolytic activity of the second component of complement (C2) in human serum. The assay is based on the recovery of hemolytic activity of normal serum which has been pretreated to inactivate endogenous C2 and then mixed with test serum containing an unknown amount of C2. 2. The pretreated serum, designated R2 reagent, is obtained by heating normal human sera under carefully standardized conditions of temperature, time, volume and type of test tube. 3. R2 reagent is incorporated into agarose together with hemolysin-sensitized erythrocytes, and spread on a plate. The test serum is placed in wells cut in the agarose and, after appropriate incubation, the diameters of the hemolytic areas are measured. The area of hemolysis is directly proportional to the logarithm of the serum concentration. As a standard for C2 functional activity, dilutions of a pool of normal sera are tested on the same plate. 4. The method is specific for C2 and can detect as little as 20% of the C2 in normal serum (about 6 micrograms C2 protein/ml). The error in reproducibility is about 3% of the mean. In normal serum, the lower confidence limit of the distribution of the C2 values (based on a sample of 80 individuals) corresponded to 70% of undiluted serum. 5. This method is suitable for use in clinical laboratories since it is simple, rapid, quantitative and inexpensive, and does not require special equipment.

Toxoplasmosis serology: an efficient hemagglutination procedure to detect IgG and IgM antibodies.

In search of an efficient but simple, low cost procedure for the serodiagnosis of Toxoplasmosis, especially suited for routine laboratories facing technical and budget limitations as in less developed countries, the diagnostic capability of Hematoxo, an hemagglutination test for toxoplasmosis, was evaluated in relation to a battery of tests including IgG- and IgM-immunofluorescence tests, hemagglutination and an IgM-capture enzymatic assay. Detecting a little as 5 I.U. of IgG antitoxoplasma antibodies, Hematoxo showed a straight agreement as to reactivity and non-reactivity for the 443 non-reactive and the 387 reactive serum samples, included in this study. In 23 cases presenting a serological pattern of acute toxoplasmosis and showing IgM antibodies, Hematoxo could detect IgM antibodies in 18, indicated by negativation or a significant decrease in titers as a result of treating samples with 2-mercapto-ethanol. However, a neat increase in sensitivity for IgM specific antibodies could be achieved by previously removing IgG from the sample, as demonstrated in a series of acute toxoplasmosis sera. A simple procedure was developed for this purpose, by reconstituting a lyophilized suspension of Protein A--rich Staphylococcus with the lowest serum dilution to be tested. Of low cost and easy to perform, Hematoxo affords not only a practical qualitative procedure for screening reactors and non-reactors, as in prenatal services, but also quantitative assays that permit to titrate antibodies as well as to identify IgM antibodies.

[Avidity of specific IgG antibodies as markers of recent primary infection caused by Toxoplasma gondii]. / Avidez de anticorpos IgG específicos como marcadores de infecção primária recente pelo Toxoplasma Gondii.

For serologically characterizing a recent primary toxoplasma infection, the low avidity of IgG specific antibodies was studied. Avidity was evaluated as the decrease of IgG antibody titers in ELISA after treating plates with 6 M urea, as a dissociating solution of low avidity antigen-antibody complexes. Sixty nine serum samples were studied, presenting characteristic patterns of recent, transitional or chronic toxoplasmosis. Serological patterns were determined according to results of IgG and IgM immunofluorescence, IgM-capture, and hemagglutination tests. Twenty three serum samples from each of the referred patterns I, II and III were titrated. For chronic toxoplasmosis infections, which presented a serological pattern III, observed decrease of titers was 3% +/- 3%. For pattern I recent toxoplasmosis sera it was 34% +/- 12%, and for transition pattern II, 12% +/- 9%. Thus, a low avidity of IgG specific antibodies can be applicable for the diagnosis of a recent toxoplasmosis infection.

[Serum antigliadin antibodies in the diagnosis and follow-up of celiac disease]. / Anticorpo sérico antigliadina no diagnóstico e seguimento da doença celíaca.

Between July 1985 and June 1990, we prospectively investigated 236 children suspected of having malabsorption syndrome. Each patient had a xylose absorption test and small intestinal biopsy. Blood samples were collected to AGA assay. The aim of the study was to evaluate the use of antigliadin antibodies test, IgG and IgA, in screening celiac disease for intestinal biopsy and in the monitoring of gluten-free diet and challenge in celiac patients. Twenty patients were diagnosed with celiac disease confirmed by three small intestinal biopsies; 12 patients were suspected of having celiac disease, with two biopsies, before and one year after a gluten-free diet; 106 patients had environmental enteropathy; 45 patients had protracted diarrhea and 56 children had failure to thrive with no gastrointestinal symptoms. The AGA test was considered a reliable test in screening for biopsy and in the differential diagnosis between celiac disease and other causes of malabsorption syndrome. The IgG AGA test had high sensitivity (90.4%) and the IgA AGA test had high specificity (92.1%) in screening for celiac disease. In the follow-up of the celiac patients the antibody levels were significantly higher during gluten containing diet than after gluten avoidance being thus a reliable test to evaluate dietary compliance.

[Standardization of immunofixation technique for the detection and identification of serum paraproteins]. / Padronização da técnica de imunofixação na detecção e identificação de paraproteínas séricas.

Diagnosis and follow up of paraproteinaemias require identification and typing of paraproteins. Immunoelectrophoresis is the most commonly used method, though a lengthy one and with low sensitivity. Immunofixation is more sensitive, faster and of easier interpretation, specially when monoclonal proteins are present in low concentration in the serum and/or urine. Immunofixation includes two steps. The first is electrophoresis; the second is immunofixation of the separated antigen by use of antiserum. The latter step is accomplished by layering the antiserum over the agarose gel immediately after electrophoretic separation of the proteins resulting in antigen/antibody precipitation. PURPOSE--The objective of this study is to standardize the technique of immunofixation and compare it to immunoelectrophoresis. METHOD--The serum of 28 patients (25 with multiple myeloma and 3 with polyclonal hypergammaglobulinaemia) was analysed and compared to 6 normal subjects. All were submitted to electrophoresis on agarose gel, immunoelectrophoresis and immunofixation. RESULTS--Dilution of the serum to produce a concentration suitable for immunofixation is critical. In our study the correct paraprotein concentration was 28 to 35 g/dl. Both methods detected and identified the paraprotein in 21 (84%) of the samples and in 2 (8%) it was not detected at all. In two of the samples, only immunofixation was able to detect and identify the paraprotein. There was not any monoclonal band observed either through the electrophoresis or immunoelectrophoresis that was not detected by the immunofixation. CONCLUSION--These results show that immunofixation is more sensitive than immunoelectrophoresis and therefore should be incorporated into diagnosis routine.

Preferential enhancement of human T cell survival "in vitro" using subthreshold concentration of phytohemagglutinin.

Cultures of human peripheral blood lymphocytes were maintained for 21 days in the presence of subthreshold concentration of PHA. The identification of T and B human lymphocytes by membrane markers showed that at day 21 of culture, the cell population surviving is constituted predominantly of T lymphocytes.

Cartilage-hair hypoplasia syndrome: immunological evaluation of two cases.

PURPOSE: Immunological evaluation of patients with cartilage-hair hypoplasia. TYPE: Prospective and retrospective studies. PLACE: Division of Allergy, Clinical Immunology and Rheumatology-Dept. of Pediatrics-"Escola Paulista de Medicina". PATIENTS: Two children with cartilage-hair hypoplasia syndrome. METHODS: Clinical and immunological evaluation. Humoral immunity (immunoglobulin levels, poliovirus antibodies, etc.) and T cell immunity (in vitro cultured lymphocytes stimulated with PHA, Con A and PWN, total T cell and subset determination) were studied. RESULTS: Cellular immunodeficiency and hypogammaglobulinemia were observed in one patient and normal values in the other. CONCLUSIONS: Immunological evaluation (cellular and humoral) should be performed in all patients with cartilage-hair hypoplasia.

Common variable immunodeficiency: a clinical and laboratory evaluation of 15 cases.

The clinical and laboratory data for 15 patients with common variable immunodeficiency (CVI) (5 females and 10 males aged 3 years and 6 months to 40 years at first examination) were evaluated. The age of onset of infectious signs and symptoms ranged from 6 months to 35 years. Recurrent pulmonary infections predominated (86.6%), followed by chronic diarrhea (46.6%). Approximately 60% of the patients with pulmonary complaints presented chronic sequelae (bronchiectasis). Two developed a polymyositis-like picture. No neoplasms were observed. All patients presented immunoglobulin levels below 300 mg/dl and absence of antibody responses to poliovirus and to hemagglutinin. Two patients were negative when tested for autoimmunity. Cell immunity tested by the lymphoproliferative response in the presence of phytohemagglutinin was normal in 11 patients and depressed in 4. A decrease in the helper T population and inversion of the OKT4/8 ratio occurred in 13. Cimetidine treatment (1200 mg/day) applied to 5 patients for 4 weeks did not produce any clinical or laboratory improvement. Gamma globulin is the treatment of choice for these patients.

Secretory IgA levels in normal and atopic individuals. Influence of breast and/or bottle feeding.

The SIgA and IgA quantification by radial immunodiffusion was carried out in the saliva of 449 normal individuals, whose ages vary from 1 day to 32 years old. SIgA was determined in an agar plate containing purified serum against SIgA of human colostrum and the IgA in commercial plates containing serum anti IgA. The SIgA values grouped in different age groups were much variable, allowing only to establish minimum critical values for each group. In the saliva of 71 patients IgA was dosed by both methods. The set of obtained data showed significant correlation (p less than 0.05). The dosage of standardized quantities of SIgA and IgA in conventional plates containing serum anti IgA, allowed to establish corresponding values similar to precipitation ring diameter. In this way, it was possible to establish a "critical value" for salivary IgA by the use of conventional plates. Thus, the IgA quantitative determination by radial immunodiffusion with antibody against serum IgA was carried out in saliva samples of normal and atopic individuals (asthma and/or rhinitis). The patients' ages varied from 1 month to 32 years old. The obtained values were grouped according to defined age group. We observed non-measurable values in 70% of the children aged less than 1 month; from then on, the values were increasing, reaching adult levels from the 6th year on. We did not observe differences between the salivary IgA levels of normal and atopic children. In children aged less than 6 months breast and/or bottle feeding (natural, mixed or artificial) there were no differences between the IgA levels observed in saliva.

Critical appraisal of the pattern of antinuclear antibodies (ANA) testing requested over a six month period at the "Escola Paulista de Medicina" (EPM), São Paulo.

In order to evaluate the pattern of ANA testing solicitation, 506 patients with ANA testing requested from July 1st. 1988 to December 31st, 1988, had their charts reviewed. These patients, randomly selected, were regularly attending the outpatient clinic at the "Escola Paulista de Medicina" (EPM). 289 patients were followed up at the Rheumatology Division (group A) and 217 patients at other clinical divisions at EPM (group B). The diseases that most frequently motivated the request for ANA test were: group A--SLE (22.5%), RA (18.0%), undefined arthropathies (6.2%), PSS and CREST (5.9%) and Raynaud phenomena (5.5%); and group B--rheumatic diseases (24.4%), nephropathies (17.1%), neuropathies (16.6%), dermopathies (7.8%), hemopathies (4.6%), pneumopathies (4.2%) and ophthalmopathies (3.7%). The positivity of ANA test in groups A and B was 32.9% and 17.5% respectively. 94 SLE patients were clinically diagnosed. The positivity of ANA and anti-dsDNA tests in this group was respectively 85.1% and 26.6%. The sensitivity and specificity of 1982 ARA revised criteria were 94.7% and 99% respectively. The likelihood ratio (LR) of a positive or a negative test was established for this population. LR of a positive test was 6.5 while for a negative test it was 0.17. The ANA test, although lacking specificity, has been commonly requested by different specialties in order to practically rule-out the diagnosis of some connective rheumatic diseases. Immunofluorescence technique (IF) using antibodies conjugated with fluorochromes. was first described by Coons et al. in 1941. This method has been used as an important diagnostic tool in routine laboratory tests ever since.(ABSTRACT TRUNCATED AT 250 WORDS)

Serodiagnosis of human cysticercosis by using antigens from vesicular fluid of Taenia crassiceps cysticerci.

Neurocysticercosis (NC), caused by the presence of Taenia solium metacestodes in tissues, is a severe parasitic infection of the central nervous system with universal distribution. To determine the efficiency of enzyme-linked immunosorbent assay (ELISA) and immunoblot with antigens of T. crassiceps vesicular fluid (Tcra) compared to standard techniques (indirect immunofluorescence test [IFT] and complement fixation test [CFT]) using T. solium cysticerci (Tso) for the serodiagnosis of NC, we studied serum samples from 24 patients with NC, 30 supposedly healthy individuals, 76 blood bank donors, 45 individuals with other non-NC parasitoses, and 97 samples from individuals screened for cysticercosis serology (SC). The sensitivity observed was 100% for ELISA-Tso and ELISA-Tcra, 91.7% for the IFT, and 87.5% for the CFT. The specificity was 90% for ELISA-Tso, 96.7% for ELISA-Tcra, 50% for IFT, and 63.3% for CFT. The efficiency was highest for ELISA-Tcra, followed by ELISA-Tso, IFT, and CFT. Of the 23 samples from SC group, which were reactive to ELISA-Tso and/or ELISA-Tcra, only 3 were positive to immunblot-Tcra (specific peptides of 14- and 18-kDa) and to glycoprotein peptides purified from Tcra antigen (gp-Tcra), showing the low predictive value of ELISA for screening. None of the samples from the remaining groups showed specific reactivity in immunoblot-Tcra. These results demonstrate that ELISA-Tcra can be used as a screening method for the serodiagnosis of NC and support the need for specific tests for confirmation of the results. The immunoblot can be used as a confirmatory test both with Tcra and gp-Tcra, with the latter having an advantage in terms of visualization of the results.