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PubMed2006

Persistently low plasma thioredoxin is associated with meningococcal septic shock in children.

OBJECTIVE: To compare plasma levels of thioredoxin (Trx), TNF-alpha and IL-1 beta in children during the acute phase of meningococcal septic shock (MSS) and in convalescence. DESIGN AND SETTING: Retrospective, observational study in the paediatric intensive care unit of a postgraduate teaching hospital. PATIENTS: Thirty-five children requiring intensive care for meningococcal sepsis; paired convalescent samples from 30 survivors (median interval between samples 62 days); 25 healthy control children. MEASUREMENTS AND RESULTS: Plasma Trx levels were significantly lower in the children with MSS, both during the acute illness (5.5 ng/ml, IQR 1.4-11.4) and in convalescence (2.5 ng/ml, IQR 0.4-6.9) than controls (18.8 ng/ml, IQR 7.9-25.0). Levels of IL-1 beta and TNF-alpha were higher in patients with acute MSS (30.3 pg/ml, IQR 3.6-63.6, and 145.9 pg/ml, IQR 31.8-278.1 respectively) than controls (3.7 pg/ml, IQR 0-36.9, and 23.8 pg/ml, IQR 0-124.3, respectively). Levels fell in convalescence (3.7 pg/ml, IQR 0-25.5, 3.7 pg/ml, IQR 0-304.8, respectively). Plasma Trx was higher in non-survivors, albeit a small group (n=5), than in survivors (n=30). Trx, IL-1 beta, and TNF-alpha levels were not correlated with predicted mortality as assessed by the paediatric risk of mortality (PRISM) score. CONCLUSIONS: Children with MSS exhibit persistently low plasma levels of Trx during acute illness and in convalescence.

Case-Control Studies↗
PubMed2000

Expression of Ki-67 antigen using monoclonal antibody MIB-1 in children with post-streptococcal glomerulonephritis.

We investigated the expression of Ki-67 antigen using monoclonal antibody MIB-1 in glomeruli and renal tubules of 21 children (18 males, 3 females) with post-streptococcal glomerulonephritis (PSGN). Patients were divided into two groups of active and convalescent phases. The active group (n=13) comprised those patients with clinical manifestations of the acute nephritic syndrome consisting of edema, hypertension, hematuria, and oliguria or those in whom percutaneous renal biopsy was performed within 4 weeks of onset of the symptoms of PSGN and those with serum C3 levels below 55 mg/dl at the time of biopsy. MIB-1 expression was considered positive when staining of endocapillary cells was observed. Of the 21 biopsies, expression of MIB-1 in glomeruli and renal tubules was observed in 14 cases (63.6%) and 20 cases (95.7%), respectively. The expression of MIB-1 in glomeruli of patients with active disease (11/13, 84.6%) was significantly higher than that of the convalescent group (2/8, 25%) (P=0.018). The cellularity in the glomeruli was more severe in the active group than the convalescent group (P=0.0475). There was a significant difference of neutrophilic infiltration in glomeruli between the active group and the convalescent group (P=0.0117). However, glomerular MIB-1 expression did not correlate with the degree of immunofluorescence, the number of neutrophils in the glomeruli on light microscopy, and the presence of subepithelial dense deposits on electron microscopy. There was no significant correlation between MIB-1 and serum C3 level. There was no significant correlation between glomerular MIB-1 expression and creatinine clearance (r=-0. 180, P=0.556) or 24-h urinary protein excretion (r=0.434, P=0.137). Our results suggest that the expression of MIB- in glomeruli in the active phase in PSGN was higher than in the convalescent phase and expression of glomerular MIB-1 appears to be related to glomerular endocapillary proliferation with exudative lesions in children with PSGN.

Adolescent↗
PubMed1996

Diagnosis of respiratory virus infections using GACELISA of urinary antibodies.

Sensitive and specific methods are needed to diagnose respiratory virus infections using body fluids such as urine that, unlike blood samples, are readily obtained by non-invasive means. Immunoglobulin G antibody capture enzyme-linked immunosorbent assays were developed for detection of antibody rises to respiratory syncytial virus and influenza A/Taiwan (H1N1) after initial quantification and adjustment of urinary IgG concentration. Of 24 elderly subjects whose sera were assayed by the complement fixation test for antibody to RSV, seven had convalescent titres > or = 32, and five had > or = 4-fold rises in titre. Acute and convalescent urines for six of these seven subjects were tested for virus-specific urinary IgG by GACELISA. Four of four persons with > or = 4-fold rises in CFT had urine ELISA convalescent to acute ratios of > or = 1.8 whereas two subjects with convalescent CF titres > 16, but no increase in serum antibody titre, had urine convalescent/acute ratios of 1.0. Ten subjects with > or = 4-fold rises in CFT or HI antibodies to influenza A/Taiwan had urine ELISA ratios of > or = 1.4 when samples taken on the day of influenza vaccination and 16 days later were compared. These preliminary observations demonstrate clinically significant rises in respiratory pathogen antibody levels between acute and convalescent urine samples, provided that total urinary IgG concentrations are quantified and then standardised.

Aged↗
PubMed1988

Changes in serum lipoprotein pattern induced by acute infections.

To study the effects of acute infections on serum lipids and lipoproteins we measured the concentration and composition of different lipoproteins, apoproteins A-I, A-II, and B, and the activities of plasma postheparin lipolytic enzymes, lipoprotein lipase (LPL) and hepatic lipase (HL) during acute and convalescence phase and after complete recovery in 72 infectious patients (33 with viral infection and 39 with bacterial infection). The mass concentrations of both low density lipoprotein (LDL) (P less than .001) and high density lipoprotein (HDL)2 (P less than .002) were reduced during acute infections due to the lowering of their cholesterol, phospholipid, and protein contents. The reduction of LDL cholesterol was maximal at the acute stage of infection (change -15%, P less than .001) while the reduction of HDL2 cholesterol was maximal during the convalescence (change -35%, P less than .001). During acute infections LDL became triglyceride-enriched (11.8 v 8.6%, P less than .0001) but cholesterol-poor (36.6 v 39.3%, P less than .0001). The ratio of HDL cholesterol/LDL cholesterol was significantly reduced during the convalescence (0.42 +/- 0.15 v 0.53 +/- 0.19, P less than .0001). The concentrations of apo A-I and apo A-II were decreased during acute infections (changes -22%, P less than .001, and -16%, P less than .001, respectively). The very low density lipoprotein (VLDL) was 18% higher during the convalescence period than after the recovery due to the elevations of VLDL triglycerides, cholesterol, and phospholipids. The activity of LPL was reduced both in the acute and convalescence phase, whereas that of HL was reduced only in the acute phase of infections.(ABSTRACT TRUNCATED AT 250 WORDS)

Acute Disease↗
PubMedDate not supplied

Serological diversity of antigens expressed on the surface of erythrocytes infected with Plasmodium falciparum.

We have studied the surface-antigen phenotypes of infected erythrocytes from children with acute falciparum malaria in the Punjab, Pakistan. Infected erythrocytes from 15 children and their homologous acute and convalescent sera, as well as hyperimmune sera from adults living in the same area, were used to analyse the serological diversity of parasite-associated antigens expressed on the surface of erythrocytes infected with Plasmodium falciparum. Analysis included agglutination, cytoadherence/inhibition of cytoadherence to melanoma cells, and rosette formation/disruption of rosettes formed between infected and non-infected erythrocytes. We found that isolate-specific antibodies were acquired by all children during convalescence and that there was a high degree of diversity of surface-antigen phenotypes. A majority of the sera either acquired or increased by 2- to 3-fold the capacity to inhibit cytoadherence and/or agglutinate the patient's own infected erythrocytes during convalescence and a strong correlation was found between these 2 activities. Hyperimmune sera from adults agglutinated and/or inhibited cytoadherence of many, but not all, of the isolates. Rosette formation was observed in 11 of the 15 isolates; 38% of the acute and 75% of the convalescent sera had anti-rosette activity on rosettes formed by the patient's own parasites. Among the isolates there was no correlation between rosette formation and binding of infected erythrocytes to melanoma cells. Our data provide good evidence that the children developed isolate-specific antibodies during convalescence from an acute attack of falciparum malaria and suggest that there was a high degree of heterogeneity of antigens expressed on the surface of infected erythrocytes.

Agglutination Tests↗
PubMed1996

Serum antibacterial and antitoxin responses in clinical cholera caused by Vibrio cholerae O139 Bengal and evaluation of their importance in protection.

Vibrio cholerae O139 Bengal strain was the causative agent of the recent epidemics of cholera in India and Bangladesh. We studied antibacterial and antitoxin immune responses in acute and convalescent phase paired sera collected from seven of these cholera patients. Significant rise in the levels of both antibacterial and antitoxin antibodies was demonstrable in the sera of convalescent cholera patients. Antibacterial antibodies, directed primarily against O139 lipopolysaccharides (LPS), belonged to IgM class, while antitoxin antibodies were of IgG and IgA class and neutralized cholera toxin. The convalescent sera, however, showed no increase in the reactivity towards V. cholerae O1 whole cells or their LPS preparation. Immunoblotting experiments revealed that the convalescent, but not the acute, phase serum recognized the truncated form of LPS characteristics of O139 strains. Convalescent serum also induced definite protection against O139, but not O1, challenge in experimental animal model. Further studies showed that such protection was probably mediated by antibodies inhibiting intestinal colonization of O139 organisms. These results suggest that critical difference(s) exists between the immunogenic somatic components of V. cholerae O1 and O139 organisms that are of considerable importance in protection against cholera.

Antibodies, Bacterial↗
PubMed2005

Adrenomedullin and total nitrite levels in children with acute rheumatic fever.

OBJECTIVE: To investigate the levels of adrenomedullin (AM) and total nitrite, a stable product of nitric oxide (NO), in children with acute rheumatic fever (ARF). DESIGN AND METHODS: Eleven children with ARF were investigated in comparison with 14 healthy controls. Adrenomedullin was detected by HPLC, while total nitrite was quantitated by the Griess reaction. RESULTS: Plasma urinary AM and total nitrite levels were significantly higher in children with ARF, irrespective of whether they were in the acute or convalescent phase of disease. Plasma AM (pmol/mL) levels were 49.19 +/- 3.23 in the acute phase, 44.52 +/- 4.26 in the convalescent phase, 35.49 +/- 3.43 in controls, and urinary AM excretion (pmol/mg creatinine) was 43.45 +/- 18.40 in the acute phase, 32.38 +/- 15.37 in the convalescent phase, and 24.84 +/- 11.38 in controls. Plasma total nitrite levels (mumol/L) were 75.37 +/- 13.13 in the acute phase, 59.81 +/- 12.78 in the convalescent phase, and 41.09 +/- 10.27 in controls. Urinary total nitrite excretion (mumol/mg creatinine) was 3.82 +/- 1.56 in the acute phase, 2.15 +/- 0.58 in the convalescent phase, and 1.33 +/- 0.61 in controls. The differences were statistically significant for all (P < 0.05). CONCLUSION: This study considered that AM and NO may have a role in the immunoinflammatory process of ARF.

Acute Disease↗
PubMed1992

Hepatic blood flow and metabolism in severe falciparum malaria: clearance of intravenously administered galactose.

1. Hypoglycaemia and lactic acidosis are important manifestations of severe falciparum malaria. To investigate hepatic gluconeogenesis in acute falciparum malaria, liver blood flow and galactose clearance were estimated in seven adult patients with moderately severe infection and seven patients with severe infection (three of whom died later). Nine patients were restudied in convalescence. 2. Liver blood flow, determined from the plasma clearance of Indocyanine Green, was lower in acute illness than in convalescence [16.1 (7.0) versus 23.9 (7.2) ml min-1 kg-1, mean (SD)], but this difference was not statistically significant (P = 0.15). There was a significant inverse correlation between admission venous plasma lactate concentrations and the liver blood flow estimated from the clearance of Indocyanine Green (rs = 0.71, P = 0.004). 3. The plasma clearance of galactose after intravenous injection was similar in the acute [15.4 (4.90) ml min-1 kg-1] and convalescent study [12.8 (2.1) ml min-1 kg-1]. The ratio of galactose clearance to Indocyanine Green clearance was significantly higher in acute disease [1.41 (0.51)] than in convalescence [0.70 (0.34)], largely because of the elevated ratios in severely ill patients [1.48 (0.50)]. 4. The rise in blood glucose concentration after galactose administration was significantly higher during acute illness [1.48 (0.72) mmol/l] than in convalescence [0.67 (0.41) mmol/l, P = 0.022], but the insulin response was similar, indicating reduced tissue insulin sensitivity. There was no significant change in the plasma concentrations of other metabolites (lactate, pyruvate, alanine and triacylglycerol) in either study. 5. These results suggest that the segment of the glycolytic pathway between galactose and glucose is unimpaired in patients with severe falciparum malaria.(ABSTRACT TRUNCATED AT 250 WORDS)

Acute Disease↗
PubMed2000

Plasma brain natriuretic peptide concentrations in patients with Kawasaki disease.

BACKGROUND: Brain natriuretic peptide (BNP) is a cardiac hormone and plasma levels of it increase in patients with congestive heart failure and in those with acute myocardial infarction. Kawasaki disease (KD) is a well-known generalized vasculitis and the most prominent features of this disease are the cardiovascular manifestations, which involve the pericardium, myocardium, endocardium and coronary arteries. It was hypothesized that the plasma concentrations of BNP in patients with KD might be increased and that plasma BNP might be a useful biological marker of cardiovascular manifestations in patients with KD. METHODS: Blood was obtained to measure and compare plasma BNP concentrations in the acute (n = 32) and convalescent (n = 35) phases of KD and in the acute phase of the patients with viral infection (n = 26), which included adenovirus, influenza, measles and herpes group virus infection. In patients with KD, two-dimensional echocardiography was performed to check for pericardial effusion and coronary arterial lesions and to measure the dimensions of the left ventricle at diastole and the shortening fraction of the left ventricle (LVSF). RESULTS: The mean plasma BNP concentration in patients with KD in the acute phase was 55.0 +/- 39.5 pg/mL, but was 6.8 +/- 7.3 pg/mL in patients with viral infection. The plasma BNP concentration in patients with KD in the acute phase was significantly higher than in patients with viral infection (P < 0.0001). In 31 cases of KD, the plasma BNP concentrations were measured both in the acute and convalescent phases. The mean plasma BNP concentration in the acute phase of KD was 55.3 +/- 40.1 pg/mL and in the convalescent phase was 5.9 +/- 5.7 pg/mL. The level of plasma BNP decreased significantly in the convalescent phase (P < 0.0001). The mean BNP level in patients with KD with pericardial effusion (n = 8) in the acute phase was 80.3 +/- 43.4 pg/mL and that in patients without pericardial effusion (n = 24) was 46.5 +/- 35.1 pg/mL. The BNP level in patients with pericardial effusion was significantly higher than that of patients without pericardial effusion (P < 0.05). There was no significant correlation between the plasma concentrations of BNP in the acute phase of KD and LVSF (r = -0.161, P = 0.39, n = 31). CONCLUSION: It was shown that the plasma BNP concentration increased in the acute phase of KD and decreased to within normal range in the convalescent phase. Further examinations are needed to clarify the mechanism by which the elevated levels of plasma BNP occur in the acute phase of KD. However, plasma BNP might be a useful biological marker of the cardiovascular manifestations in patients with KD.

Acute Disease↗
PubMed1987

Serum antibody responses to individual viral polypeptides in human rotavirus infections.

A radioimmunoprecipitation assay (RIPA) was used to study the serum antibody responses to individual polypeptides that developed after infection with viruses from human rotavirus subgroups I and II. Paired sera from eight children (1 to 8.5 years of age) were used in the study. Although all of the eight acute sera were negative by the complement fixation test, four of them were positive by RIPA, indicating a previous infection by rotavirus. A significant difference in the number of polypeptides immunoprecipitated was seen among the convalescent sera. The number of polypeptides immunoprecipitated was found to be related to previous infection experience. At most, ten different polypeptides were immunoprecipitated: seven structural polypeptides VP1 to VP7 and three non-structural polypeptides, NS1, NS2 and NS3. No sera immunoprecipitated VP8 or VP9. Acute sera positive by RIPA immunoprecipitated up to five polypeptides, VP1, VP2, VP3, VP4 and VP6. One of the non-structural proteins (NS2) was found to be particularly immunogenic, since antibodies to this polypeptide were detected in several convalescent sera. Among the structural proteins VP2 and VP6 were found to be the two immunodominant polypeptides which were recognized by all convalescent sera. Only three convalescent sera immunoprecipitated VP7, the major type-specific antigen responsible for inducing neutralizing antibodies. Three of four originally seronegative children with no reactivity in the convalescent sera to VP7 developed neutralizing antibodies to a single serotype. One child developed antibodies to two serotypes.

Antibodies, Viral↗
PubMed1994

Antibody-dependent enhancement of respiratory syncytial virus infection by sera from young infants.

Respiratory syncytial virus (RSV) convalescent-phase sera and control sera from both infants ( < 6 months) and older individuals (1.5 to 90 years) were assayed for RSV-specific antibodies by neutralization, in vitro enhancing activity, and immunoprecipitation. Enhancement of RSV infection in U937 cells was demonstrated with convalescent-phase sera and was shown to be dependent on Fc receptors by blocking with human immunoglobulin G (P < 0.01). Convalescent-phase sera from infants enhanced infection at concentrations closer to physiological ones (10(-1) to 10(-3) dilutions of serum), while convalescent-phase sera from older individuals enhanced infection only at much lower concentrations (10(-3) to 10(-6) dilutions of serum; P < 0.01). To our knowledge, this is the first report of RSV-enhancing antibody activity in the sera of infants. The observed enhancing activity and the low neutralizing antibody levels are confined mostly to convalescent-phase sera from infants aged 0 to 6 months, suggesting that these factors may contribute to the increased severity of RSV disease frequently encountered in young infants.

Adolescent↗
PubMed2004

Analysis of eight commercial enzyme immunoassay tests for detection of antibodies to Mycoplasma pneumoniae in human serum.

Mycoplasma pneumoniae is an important etiologic agent of primary atypical pneumonia in children and adults. The diagnosis of M. pneumoniae infection is commonly confirmed through serologic testing. In this study, we used paired sera from 51 patients (all with confirmed M. pneumoniae infection and positive complement fixation [CF] titers) to compare the results of eight enzyme immunoassays (EIAs) available commercially in the United States. We compared two single-use EIAs and six plate-type EIAs. Results from acute-phase sera ranged from only 7 (14%) positive by ImmunoWELL (GenBio) immunoglobulin M (IgM) EIA to 23 (45%) positive by Zeus IgG EIA. When both the acute-phase and convalescent-phase serum samples were examined, positive results ranged from 20 (39%) by the ImmunoWELL (GenBio) IgM assay to 45 (88%) positive by the Remel IgG-IgM EIA. In this study, the single-use EIAs by Remel and Meridian were more reliable than were the plate-type EIAs. Among the plate-type EIAs, the Zeus and DiaSorin assays (which detect antibodies to protein antigens) were more sensitive than the ImmunoWELL assay (which detects antibodies to glycolipid antigens). In general, IgG EIAs on convalescent-phase sera were more concordant with one another than were IgM EIAs with one another. Scatter plot analysis of convalescent-phase sera showed that, as the CF titer dropped, the IgM assays identified fewer positive convalescent-phase sera. In contrast, the IgG assays provided fairly consistent positive results for convalescent-phase sera with CF titers of 64 and above. Results of individual tests and overall limitations of serodiagnostics for M. pneumoniae infections are discussed.

Antibodies, Bacterial↗
PubMed1980

Kinetics of peripheral blood leukocyte alterations in Thai children with dengue hemorrhagic fever.

Peripheral leukocytes from 16 Thai children with dengue hemorrhagic fever were examined to determine the leukocyte composition on the day of presentation and on convalescent days 15 and 30. Mononuclear cells were isolated each time, and the concentrations of T, B, Fc receptor-bearing, and "null" cells were determined. On the day of hospitalization, in comparison to convalescent values, there was a significant increase in total lymphocytes, primarily due to concentrations of atypical lymphocytes. There was a significant loss of T cells with an increase in non-T, non-B, non-Fc receptor-bearing null cells. There were no changes in the concentrations of monocytes, B cells, or Fc receptor-bearing cells when acute and convalescent values were compared. During the convalescent period, a progressive increase in eosinophils was noted. Also, on day 15 but not on day 30 of the convalescent period, an increase was observed in the total leukocyte number due to an increase in granulocytes. There results indicate that in Thai children with dengue hemorrhagic fever, there are major shifts within several component cell subpopulations of the immune system.

Dengue↗
PubMed1993

Pneumocystis carinii organisms obtained from rats, ferrets, and mice are antigenically different.

Pneumocystis carinii infections were developed in animals immunosuppressed by dexamethasone treatment either from activation of latent infection (ferret) or by transtracheal inoculation with P. carinii-infected lung tissue from the homologous species (rat or mouse). Convalescent-phase antisera were obtained by stopping dexamethasone treatment after 2 to 4 weeks and allowing animals 5 to 8 weeks for recovery. P. carinii harvests from infected lungs were purified by differential filtration, solubilized in buffer containing urea, sodium dodecyl sulfate (SDS), and 2-mercaptoethanol, subjected to SDS-polyacrylamide gel electrophoresis, and blotted to polyvinylidene difluoride sheets for Western immunoblot analysis. These lung preparations are hereafter referred to as P. carinii antigens. Convalescent-phase antisera from each animal species were reacted on Western blots of P. carinii antigens prepared from organisms isolated from rats, ferrets, or mice. Each combination of P. carinii antigens and antisera from the same species of animal reacted with three or more P. carinii antigen proteins. Convalescent-phase mouse antisera reacted with P. carinii antigens from mice but not rats or ferrets. Convalescent-phase rat antisera reacted with P. carinii antigens from rats and mice but not ferrets, and convalescent-phase ferret antisera showed reactions with ferret and mouse P. carinii antigens but not rat antigens. These findings indicate antigenic differences among P. carinii strains infecting these animals.

Animals↗
PubMed2004

Analysis of serum cytokines in patients with severe acute respiratory syndrome.

Severe acute respiratory syndrome (SARS) is an acute infectious disease of the respiratory system. Although a novel coronavirus has been identified as the causative agent of SARS, the pathogenic mechanisms of SARS are not understood. In this study, sera were collected from healthy donors, patients with SARS, patients with severe SARS, and patients with SARS in convalescence. The serum concentrations of interleukin-1 (IL-1), IL-4, IL-6, IL-8, IL-10, tumor growth factor beta (TGF-beta), tumor necrosis factor alpha (TNF-alpha), and gamma interferon (IFN-gamma) were measured by enzyme-linked immunosorbent assays (ELISA). The concentrations of IL-1 and TNF-alpha were not significantly different in different groups. The IL-6 concentration was increased in SARS patients and was significantly elevated in severe SARS patients, but the IL-6 concentrations were similar in convalescent patients and control subjects, suggesting that there was a positive relationship between the serum IL-6 concentration and SARS severity. The concentrations of IL-8 and TGF-beta were decreased in SARS patients and significantly reduced in severe SARS patients, but they were comparable in convalescent SARS patients and control subjects, suggesting that there was a negative relationship between the IL-8 and TGF-beta concentrations and SARS severity. The concentrations of IFN-gamma, IL-4, and IL-10 showed significant changes only in convalescent SARS patients. The IFN-gamma and IL-4 levels were decreased, while the levels of IL-10 were increased, and the differences between convalescent SARS patients and other patient groups were statistically significant. These results suggest that there are different immunoregulatory events during and after SARS and may contribute to our understanding of the pathogenesis of this syndrome.

Adolescent↗
PubMed1992

Antibodies to shiga holotoxin and to two synthetic peptides of the B subunit in sera of patients with Shigella dysenteriae 1 dysentery.

Acute- and convalescent-phase sera from 18 Thai patients and convalescent-phase sera from two Israeli patients and one Bangladeshi patient with Shigella dysenteriae 1 (Shiga) dysentery were tested by enzyme-linked immunosorbent assay to detect antibodies that bind S. dysenteriae lipopolysaccharide (LPS), Shiga holotoxin, or two synthetic peptides representing epitopes from the B subunit of Shiga toxin. Paired sera from 24 Maryland adults with Shigella flexneri 2a or Shigella sonnei diarrhea served as negative controls. Of the 16 paired Thai serum samples tested for immunoglobulin G LPS antibody, 10 had greater than or equal to 4-fold rises (the two subjects with the highest convalescent-phase titers exhibited toxin-neutralizing activity); acute-phase specimens from four of the remaining six individuals already had elevated Shiga LPS titers in their acute specimens ranging from 1:800 to 1:12,800. Similarly, convalescent-phase sera from the two Israeli patients and the Bangladeshi patient revealed LPS titers of 1:800 to 1:3,200. In contrast, none of the Maryland volunteers with S. flexneri or S. sonnei diarrhea manifested rises in Shiga anti-LPS (P less than 0.00001 versus 10 of 16 Thai patients). Only 4 of the 18 Thai patients had significant rise in antibody to purified Shiga toxin, while one of the two Israeli patients and the one Bangladeshi patient had elevated convalescent-phase titers. None of the sera that reacted with Shiga holotoxin had antibody that bound to the peptides. This report, which describes a search for serum antibodies that bind Shiga toxin in patients with Shiga dysentery, demonstrates such antibodies in only a minority of patients with bacteriologically confirmed disease. During Shiga dysentery, Shiga toxin may be elaborated in such small quantities in vivo that it fails to elicit an immune response in most patients even though it may exert biological effects. In this behavior Shiga toxin resembles tetanus toxin, another potent exotoxin that fails to elicit antitoxic responses in people who recover from clinical tetanus.

Adolescent↗
PubMed1998

Videofunduscopy and videoangiography using the scanning laser ophthalmoscope in Vogt-Koyanagi-Harada syndrome.

AIM: To observe pathophysiological changes in patients with Vogt-Koyanagi-Harada (VKH) syndrome using the scanning laser ophthalmoscope (SLO) to perform videofunduscopy, and indocyanine green (ICG) and fluorescein videoangiography. METHODS: 18 patients diagnosed with VKH syndrome were studied. 15 patients were examined in both acute and convalescent phases, and three patients were examined in the convalescent phase only. Retrospective review of charts was performed to obtain data on visual acuities, clinical findings, and results of cerebrospinal fluid cytology and histocompatibility leucocyte antigen D locus testing. RESULTS: Videofunduscopy revealed abnormalities in the central macula at the level of the retinal pigment epithelium or choroid in 40% of patients in the acute phase and 83% of patients in the convalescent phase. ICG videoangiography showed irregular hypofluorescence (80%), slow or patchy filling (67%), indistinct or fewer choroidal vessels (73%), filling defects (73%), and focal leakage (33%) in patients in the acute phase. These changes improved with systemic corticosteroid treatment, although at least one ICG videoangiographic abnormality persisted into the convalescent phase in 83% of patients in the absence of clinical inflammation. In contrast, fluorescein videoangiography revealed fewer and decreased severity of abnormalities, with greater resolution in the convalescent phase when compared with ICG videoangiography. CONCLUSIONS: SLO videofunduscopy and videoangiography revealed numerous abnormalities in patients with VKH syndrome, many of which persisted well after clinical recovery, suggesting the development of permanent morphological changes in the fundus. ICG videoangiography was more sensitive than fluorescein videoangiography in delineating abnormalities in layers deep to the sensory retina.

Acute Disease↗
PubMed1996

Local entrapment of interferon gamma in the recovery from Shigella dysenteriae type 1 infection.

In healthy controls (n = 8) living in shigella endemic areas, accumulation of interferon gamma (IFN gamma) in the epithelial lining was seen in the rectal tissues. At the single cell level, however, few or no IFN gamma protein producing cells or mRNA expressing cells were detected at that site indicating the involvement of the whole large intestine in the production of IFN gamma in controls. Persistent numbers of IFN gamma producing cells were detected in the rectum of patients with Shigella dysenteriae type 1 infection (n = 8) throughout the course of disease with a tendency to increase in the convalescent stage. A significantly increased extra cellular deposition of secreted IFN gamma in tissue was seen in convalescence when compared with the acute stage (p < 0.05). In addition, enzyme immunoassay showed increased stool concentration of IFN gamma in patients at the convalescent stage as well as in healthy controls. In situ hybridisation confirmed the results by showing increased frequency of IFN gamma mRNA containing cells at the late stage of the disease (p < 0.05). Extensive message for IFN gamma was evident in cells in the lamina propria with no detectable transcripts in the surface epithelium. A colocalisation of IFN gamma with the IFN gamma receptor expression, predominantly found in the epithelial lining was detected by immunohistochemistry. Semiquantitative evaluation by computerised image analysis showed a gradual increased expression of IFN gamma and its corresponding receptor in the convalescent stage of shigellosis. This suggested progressive entrapment and binding of IFN gamma to its specific receptor at the local site. The enhanced surface expression of IFN gamma receptor evident at the convalescent stage of shigellosis was comparable to the constitutive level of expression in the healthy subjects. Thus, immunity to shigellosis correlated to up-regulation of IFN gamma production and expression of IFN gamma receptor.

Acute Disease↗