Clinical factors associated with negative urinary antigen tests implemented for the diagnosis of community-acquired pneumococcal pneumonia in adult patients

This study investigated clinical factors associated with negative urinary antigen tests [UAT] implemented for the diagnosis of pneumococcal community-acquired pneumonia [CAP] in adult patients. We reviewed the medical records of 755 adult patients who completed the UAT in our hospital between 2009 and 2012. Of these, we evaluated 63 patients with bacteriologically confirmed definite pneumococcal CAP [33 were UAT-positive, and 30 were UAT-negative]. There was no significant difference between the UAT-positive and the UAT-negative patients regarding age, dehydration, respiratory failure, orientation, blood pressure [ADROP] score [the CAP severity score proposed by the Japanese Respiratory Society], gender, white blood cell counts, liver/kidney function tests, or urinalysis. However, serum C-reactive protein [CRP] concentrations were 31% lower in the UAT-negative patients than in the UAT-positive patients [p = 0.02]. Furthermore, the prothrombin time-international normalized ratio was 50% higher in the UAT-negative patients than in the UAT-positive patients, although the difference did not reach statistical significance [p = 0.06]. The prevalence of comorbidities was similar in both UAT-positive and UAT-negative patients. However, warfarin had been prescribed in 8 [27%] of the UAT-negative patients compared to only 1 [3%] of the UAT-positive patients [odds ratio = 11.6; p = 0.01]. These results suggested that low serum CRP concentrations and the use of warfarin increased the possibility with which false-negative UAT results occurred in these patients with pneumococcal CAP

Anti-leishmanial polyclonal antibodies to assess the performance characteristics of leishmanial antigen detection ELISA

The polyclonal anti bodies raised in rabbits against amastigote antigen extract were purified and fractionated, and IgG class antibodies and from the same antibodies, a peroxidase conjugate [labeled antibodies] reagent were prepared. The antibodies and the labeled antibodies were analyzed for efficacy of the homologous extracted antigens by capture ELISA. The titration curves of the anti-amastigote IgG antibody against extracted antigens showed that both free antibody and corresponding labeled antibody reacted with the original amastigote antigens. Further analysis involved the interaction between the antibody and two leishmanial stages; mammalian amastigote and infective promasitgote by immunoflourescene technique. The strong interaction was not only with surface antigenic components of the stages but also with their internal components. Capture-ELISA system was done to detect specific leishmanial antigens in urine and sera from visceral leishmaniasis patients [VL]. Most of the urine samples were positive [90% sensitivity] for leishmanial antigens without cross-reactivity [100% specificity] with any other tested samples from heterologous parasitic infections. But, only 61% sensitivity and 53% specificity were obtained when the capture ELISA was done to detect the specific leishmanail antigens in sera from VL

Ceftriaxone Induced Immune Hemolytic Anemia: Detection of Drug-dependent Antibody by Ex-vivo Antigen in Urine

There have been a few reported cases of immune hemolytic anemia induced by ceftriaxone. We encountered a patient with immune hemolytic anemia that seemed to be stimulated by a degradation product of ceftriaxone. The patient's direct antiglobulin test was positive only for C3d, and no ceftriaxone-dependent antibodies were detectable in the patient's serum. To demonstrate the presence of the ceftriaxone-induced antibodies, an ex-vivo antigen in urine was obtained from the patient. In addition, we prepared a 1 mg/mL suspension solution of ceftriaxone, and group AB serum as a complement source. Using several combinations of the above reactants, the indirect antiglobulin test was performed. Only the indirect antiglobulin test using the patient's serum with the ex-vivo urine antigen was found to be positive. Other combinations were not reactive. To our knowledge, this is the first reported case in Korea, in which the causative antibody appeared to be stimulated solely by a degradation product of ceftriaxone.

Ceftriaxone Induced Immune Hemolytic Anemia: Detection of Drug-dependent Antibody by Ex-vivo Antigen in Urine

There have been a few reported cases of immune hemolytic anemia induced by ceftriaxone. We encountered a patient with immune hemolytic anemia that seemed to be stimulated by a degradation product of ceftriaxone. The patient's direct antiglobulin test was positive only for C3d, and no ceftriaxone-dependent antibodies were detectable in the patient's serum. To demonstrate the presence of the ceftriaxone-induced antibodies, an ex-vivo antigen in urine was obtained from the patient. In addition, we prepared a 1 mg/mL suspension solution of ceftriaxone, and group AB serum as a complement source. Using several combinations of the above reactants, the indirect antiglobulin test was performed. Only the indirect antiglobulin test using the patient's serum with the ex-vivo urine antigen was found to be positive. Other combinations were not reactive. To our knowledge, this is the first reported case in Korea, in which the causative antibody appeared to be stimulated solely by a degradation product of ceftriaxone.

Detection of circulating schistosome antigens in serum and urine of schistosomiasis patients and assessment of cure by monoclonal antibody

From a panel of monoclonal antibodies [MAb], an IgM monoclonal antibody [7F1/6B] reactive with repetitive epitopes on S. Mansoni soluble egg antigen was selected. This MAb was employed both as antigen capture and detection antibody in a sandwich ELISA and had a detection limit <1 ng S. mansoni SEA/mi. Serum and urine samples were collected from rural students who had S. mansoni [169 subjects] or mixed S. mansoni and S. hematobium [64 subjects] infections. Samples were collected before and at 4, 8 and 12 weeks after praziquantel therapy. Circulating schistosome antigens [CSA] were demonstrated in 90% of sera and 97% of urine samples of S. mansoni group and in 91% of sera and 100% of urine samples of mixed infection group. All sera from 29 uninfected individuals, 30 patients with other parasites and 70% of 55 S. hematobium-infected subjects were negative in this assay. CSA level in serum and urine samples correlated positively with the number of S. mansoni eggs/g stool in both groups. A significant reduction in CSA level was observed in serum and urine samples after praziquantel therapy. By 12 weeks post-treatments, negativity was 98% in sera and 97% in urine of S. mansoni-infected group and 98% in sera and 91% in urine of mixed infection group. The data demonstrated that the use of MAb 7F1/6B for the detection of CSA provides a sensitive method of immunodiagnosis of schistosomiasis and monitoring of cure