Antigen Detection Rate Research Articles

Development of Serum Plate Agglutination Antigen using Mycoplasma gallisepticum Field Isolate

Mycoplasma gallisepticum is an important pathogen responsible for respiratory tract infections in poultry. Clinical manifestation of disease varies from mild respiratory infection to chronic respiratory disease (CRD) in case of co-infections with other viral or bacterial pathogens. Mycoplasma infections cause huge economic losses due to reduction in hatchability and egg production as well as due to increased morbidity and mortality in a flock. Early screening of infection is done by using serological assays including Serum Plate Agglutination Assay (SPA) and Enzyme Linked Immunsorbent Assay (ELISA). The present study was aimed to prepare SPA antigen using M. gallisepticum isolate recovered from the field. In house developed antigen was compared with commercially available antigen using sera collected from the suspected flocks. Results revealed 205/300 (68.35%) positive reactions using locally developed antigen and 198/300 (66%) positive reactions while using commercially available imported antigen. After statistical analysis by using Fisher’s exact test, it was inferred that difference between detection rate of both antigens was non-significant (P =1.0000). Local antigen was assessed for cross reactivity and it gave suitable results till four months. Local antigen appears to provide a cheaper and easy method for initial screening of M. gallisepticum infection.

Evaluation of the efficacy of urine-based lipoarabinomannan antigen test in the diagnosis of pulmonary tuberculosis

Objective: To analyze the diagnostic efficacy of urinary lipoarabinomannan (LAM) antigen detection method in tuberculosis patients, and to provide an experimental basis for the clinical application of urinary LAM kit in China. Methods: From March to May 2023, 228 patients with lung diseases [134 male, 94 female, age 20-82 (44.8±16.7) years] were prospectively collected in Beijing Chest Hospital, Capital Medical University, including 143 pulmonary tuberculosis patients and 85 non-tuberculosis patients. Urine and sputum samples from patients were collected for traditional etiological detection and urinary LAM antigen detection. The screening results of each positive detection combination were analyzed, and the difference analysis and regression analysis were performed. Results: The detection sensitivity and specificity of the urinary LAM kit were 46.2% (95%CI: 37.9%-54.7%) and 96.5% (95%CI: 89.3%-99.1%), respectively, with an overall coincidence rate of 64.9%. The detection rate of LAM antigen detection and GeneXpert MTB/RIF (Xpert) combined (60.8%, 87/143) was significantly higher than that of Xpert alone (49.7%, 71/143), and the difference was statistically significant (P<0.05). The results of risk factor analysis showed that the risk of negative urinary LAM antigen test results increased significantly as the bacterial load decreased. Conclusions: Urine LAM antigen detection method has a high specificity and can be combined with traditional methods to effectively improve the detection rate. Urinary LAM antigen detection method still has limitations, such as the influence of bacterial load and the inability to distinguish nontuberculosis mycobacteria samples, which needs further experimental verification.

Characteristics of intussusception among children in Hokkaido, Japan, during the pre- and post-rotavirus vaccine eras (2007-2016).

To analyse the epidemiology of intussusception in Hokkaido Prefecture, Japan during a 10-year period spanning the introduction of the rotavirus (RV) vaccine (2007-2016). Using a standard questionnaire, a retrospective surveillance was conducted across 17 hospitals with paediatric beds in Hokkaido Prefecture. We compared the data between the pre-vaccine era (2007-2011) and post-vaccine era (2012-2016). In total, 208 and 110 intussusception cases were in the pre- and post-vaccine eras, respectively. A significant reduction of the intussusception incidence in children aged <1 year was observed from the pre- to the post-vaccine era (102.4-56.5 per 100 000 infants; incidence rate ratio, 0.55; p=0.004). There was a relatively high-positive RV antigen detection rate (29.4%, 5/17) during the RV epidemic period in Japan (March-May) in the pre-vaccine era. None of the intussusception cases in the 31 patients with a history of RV vaccination occurred within 1 month after the administration of an RV vaccine dose. The incidence of intussusception in children aged <1 year decreased significantly after RV vaccine introduction in Japan. Another survey is needed to determine how the incidence of intussusception has changed further since the introduction of routine RV vaccination in 2020.

Evaluation of a rapid diagnostic test for detection of SARS-CoV-2 antigen in nasopharyngeal swabs

Background and aims: Rapid and accurate diagnosis is essential to limit the spread of SARS-CoV-2 and for patient’s management. Currently, real-time reverse transcription polymerase chain reaction (RT-PCR) is the recommended laboratory test to detect SARS-CoV-2. However, the requirement of special instruments and skilled personnel have limited the use of this technique. Recently, several rapid antigen detection tests have been developed and used as frontline. The aim of this work was to assess the performances of STANDARD F COVID-19 Ag FIA Kit, a rapid fluorescence immunoassay for the detection of SARS-CoV-2 nucleoprotein antigens, in comparison to RT-PCR.Materials and methods: Twenty-three nasopharyngeal swabs were collected and tested. Results: Among the 20 positive RT-PCR samples, 9 were detected by the immunofluorescence assay, reporting an overall sensitivity of 45%. The sensitivity increased to 64% in the case of a high viral load, where all three target genes, RdRp, N, and E, were detected by RT-PCR. Conclusions: A better antigen detection rate is associated with low Cycle threshold values which are inversely related to the viral load. STANDARD F COVID-19 Ag test cannot be considered as the frontline assay for COVID-19 diagnosis, but it might be used in association with clinical signs of patients to reduce the number of RT-PCR testing.

Low performance of rapid antigen detection test as frontline testing for COVID-19 diagnosis.

Ensuring accurate diagnosis is essential to limit the spread of SARS-CoV-2 and for the clinical management of COVID-19. Although real-time reverse transcription polymerase chain reaction (RT- qPCR) is the current recommended laboratory method to diagnose SARS-CoV-2 acute infection, several factors such as requirement of special equipment and skilled staff limit the use of these time-consuming molecular techniques. Recently, several easy to perform rapid antigen detection tests were developed and recommended in some countries as the first line of diagnostic. The aim of this study was to evaluate the performances of the Coris COVID-19 Ag Respi-Strip test, a rapid immunochromatographic test for the detection of SARS-CoV-2 antigen, in comparison to RT-qPCR. 148 nasopharyngeal swabs were tested. Amongst the 106 positive RT-qPCR samples, 32 were detected by the rapid antigen test, given an overall sensitivity of 30.2%. All the samples detected positive with the antigen rapid test were also positive with RT-qPCR. Higher viral loads are associated with better antigen detection rates. Unfortunately, the overall poor sensitivity of the COVID-19 Ag Respi-Strip does not allow using it alone as the frontline testing for COVID-19 diagnosis.

A prospective randomized trial of povidone-iodine suppository before transrectal ultrasonography-guided prostate biopsy.

Objectives:To investigate a way to reduce infectious complication after transrectal ultrasonography-guided prostate biopsy (TRUS-Bx), we planned a randomized trial to determine whether the use of the povidone-iodine suppository is effective in preventing infectious complications.Methods:This study prospectively assessed 250 patients who underwent TRUS-Bx during December 2014 and May 2016. Clinical questionnaire responses and safety were evaluated. Povidone-iodine suppository after glycerin enema was performed 1 to 2 hours before TRUS-Bx. Both groups received the prophylactic antibiotics (ceftriaxone 2.0 g) 30 to 60 minutes before TRUS-Bx. No antibiotics were prescribed after TRUS-Bx.Results:The 120 were assigned in the treatment group using povidone-iodine suppository and 130 were assigned in the control group. There was no significant difference of clinicopathologic features including age, prostate-specific antigen and cancer detection rate in both groups (P > .05). No infectious and non-infectious complications were reported in both groups. Povidone-iodine suppository-related side effects were not reported. No significant differences in international prostate symptom score, sexual health inventory for men score, and European Organization for Research and Treatment of Cancer Quality of Life questionnaire scores were found between the 2 groups (P > .05). No changes in each questionnaire scores between before and after TRUS-Bx were observed.Conclusions:Despite satisfying the predefined sample size, we could not prove the hypothesis that the use of povidone-iodine suppositories after TRUS-Bx would reduce infectious complications. A large-scale, multicenter, prospective study is needed to fully evaluate the clinical efficacy and safety of povidone-iodine suppository prior to TRUS-Bx.

Detection and allergen analysis of serum IgE in pediatric patients with chronic urticaria.

Objective:To detect the serum IgE and allergen-specific IgE levels of pediatric patients with chronic urticaria, and to analyze the distribution characteristics of allergens.Methods:Ninety-six patients with chronic urticaria admitted in our hospital, which were not administered antihistamine 10 days before detection or glucocorticoid 20 days before detection, were selected. Their serum IgE levels were measured and 34 antigens were analyzed.Results:Ninety-two of the ninety-six patients were detected as serum IgE positive (positive rate: 95.83%). The positive serum IgE levels did not significantly change along with season (P>0.05). The positive detection rate of antigens was 95.83% (92/96), and the top five potent antigens included house dust mite, flour mite, histamine, egg yolk and egg white.Conclusion:Dust mite, as the most common antigen for pediatric patients with chronic urticaria, is prone to variations of specific IgE positive rate along with season. The results may be associated with the persistent warm and humid climate in this region.

Detection of specific Chlamydia pneumoniae and cytomegalovirus antigens in human carotid atherosclerotic plaque in a Chinese population.

To explore the relationship between certain pathogens, such as chlamydia pneumonia (Cpn) and cytomegalovirus (CMV), and carotid atherosclerosis (AS) in a Chinese population.Twenty-five carotid atherosclerotic stenosis patients from the Beijing Tiantan Hospital (affiliated with Capital Medical University) participated in the study. After undergoing digital subtraction angiography (DSA) and/or computed tomography angiography (CTA), the degree of carotid artery stenosis was over 70% in all cases, and the patients underwent carotid endarterectomy. Plaque specimens were obtained during surgery. The streptavidin-peroxidase (SP) method was used to test the Cpn and CMV antigens in the specimens, and the relationship between the Cpn and CMV pathogen infections and AS was analyzed based on the test results. In the group of 25 carotid atherosclerotic specimens, the detection rate of the Cpn-specific antigens was 84.0% (21/25). In the control group, the detection rate was 13.3% (2/15) in the ascending aortic intima. Thus, the between-group difference was significant (P<0.01). The CMV-specific antigen detection rate was 72.0% (18/25) using the same experimental group specimens, and the detection rate was zero in the control group. Thus, there were significant between-group differences (P<0.01). Due to the high detection rate of Cpn- and CMV-specific antigens in carotid atherosclerotic plaque in a Chinese population, it can be inferred that pathogens such as Cpn and CMV are one factor associated with carotid atherosclerosis.

Clinical value of a rapid respiratory syncytial virus antigen detection in point-of-care testing

Objective: To evaluate the clinical value of a rapid respiratory syncytial virus (RSV) antigen detection in point-of-care testing (POCT). Method: A total of 209 specimens, including 78 throat swabs (TS) and 131 nasopharyngeal aspirates (NPAs), were collected from inpatients who visited the Children's Hospital Affiliated to the Capital Institute of Pediatrics and were diagnosed as acute respiratory infection from 5 January to 7 February, 2015. These specimens were tested for RSV by a rapid antigen detection kit which was compared with reverse transcription polymerase chain reaction (RT-PCR) and direct immunofluorescence assay (DFA) for RSV detection. Result: Compared with DFA for NPAs, the sensitivity and specificity of rapid antigen detection were 83.9% and 97.3%, respectively, with Kappa value of 0.86; Compared with RT-PCR, the sensitivity (NPAs, 74.2%; TS, 77.8%) and specificity (NPAs, 100.0%; TS, 92.0%) of rapid antigen detection were high, too, with Kappa value of 0.74 in NPAs and 0.62 in TS. However, the RSV positive rate of rapid antigen detection in TS (21.7%) from pediatric patients with acute lower respiratory tract infection was lower than that in NPAs (78.3%), as well as that of RT-PCR (7.3% in TS verse 78% in NPAs). The RSV rapid antigen detection kit can be finished in about 10 minutes. Conclusion: With characteristics of high specificity, high sensitivity, being rapid, efficient and easy to operate in comparison with DFA and RT-PCR, RSV rapid antigen detection in this study is suitable for POCT. For pediatric patients with acute respiratory tract infection, NPA was better than TS for RSV detection.

The Dynamics of the Epidemiological Situation of Tick Borne Encephalitis in the Far East

We have presented a comparative analysis of morbidity and mortality in the tick-borne encephalitis (TBE) in the south of the Russian Far East in the period 1980 - 2014. In the period from 2008 to 2014 using the enzyme-linked immunoassay (ELISA) was examined 10,599 copies ticks or leukocyte fraction of blood (n = 5561) of people who indicate to the fact of tick bites. Blood samples and ticks positive in ELISA additionally examined by PCR and virus isolation. Under diagnosis of TBE cases in the 1980s resulted in lower figures morbidity and mortality artificially excessive to 39% (average 28%). In the 1990s there was a sharp rise in the incidence of TBE (median 15.3% mortality). In the 2000s there was a trend to a decrease in the number of cases and deaths (average case fatality rate of 6.3 -10.5%). The incidence rate for 35-year follow-up period ranged from 0.85 to 9.88 per 100 thousand population, mortality was 14.8 ± 0.7%. The degree of danger of the epidemic on TBE synchronously reflected in the rate of antigen detection of TBE virus in humans and ticks attached themselves. In the year’s high morbidity and mortality (in 2009 and 2010) antigen detection in ticks and in human blood reached a maximum. Isolated from the blood of these patients three TBE virus strains indicated that only a complete virus capable of replicating determines the variety clinical forms of the infection.

Relationship between prostate-specific antigen kinetics and detection rate of radiolabelled choline PET/CT in restaging prostate cancer patients: a meta-analysis

The aim of the article was to systematically review published data about the relationship between prostate-specific antigen (PSA) kinetics, including PSA doubling time (PSAdt) and PSA velocity (PSAvel), and detection rate (DR) of positron emission tomography/computed tomography (PET/CT) using radiolabelled choline in restaging prostate cancer (PCa). A comprehensive literature search of studies published through July 2013 regarding the relationship between PSA kinetics and DR of radiolabelled choline PET/CT was carried out. Furthermore, a meta-analysis was performed in order to establish the DR of radiolabelled choline PET/CT using different cut-off values of PSAdt (≤ or >6 months) and PSAvel [>1 or ≤1 ng/(mL year) and >2 or ≤2 ng/(mL year)]. Moreover, a pooled analysis to establish whether PSAdt and PSAvel (using the abovementioned cut-off values) may predict positive PET/CT results was carried out. Fourteen articles were selected. The pooled DR of radiolabelled choline PET/CT in restaging PCa was 58% [95% confidence interval (CI) 55-60]. Most articles reported a relationship between PSA kinetics and DR of PET/CT. Pooled DR of radiolabelled choline PET/CT increased to 65% (95% CI 58-71) when PSAdt was ≤6 months and to 71% (95% CI 66-76) and 77% (95% CI 71-82) when PSAvel was >1 or >2 ng/(mL year), respectively. PSAdt ≤6 months and PSAvel >1 or >2 ng/(mL year) proved to be relevant factors in predicting the positive result of radiolabelled choline PET/CT. Due to the strong relationship between PSA kinetics and DR of radiolabelled choline PET/CT, beyond PSA values, PSAdt and PSAvel should be taken into account in the selection of PCa patients who should undergo radiolabelled choline PET/CT for restaging.

High occurrence of Entamoeba histolytica in the municipalities of Ariquemes and Monte Negro, State of Rondônia, Western Amazonia, Brazil

Entamoeba histolytica infections were investigated in residents of the Ariquemes and Monte Negro municipalities in Rondônia State, Brazil. Stool samples of 216 individuals were processed by the spontaneous sedimentation method and analyzed by microscopy for detection of the E. histolytica/E. dispar complex, followed by the immunoassay method using an enzyme-linked immunosorbent assay-based kit for the E. histolytica stool antigen. E. histolytica/E. dispar cysts were present in 61% (50/82) and 44% (59/134) of the samples from Ariquemes and Monte Negro respectively, with a significant difference in the occurrence of infection between the two populations [p < 0.05; χ2 = 5.2; odds ratio = 2.0 (1.1 - 3.6)]. The E. histolytica antigen detection rate was 36.6% (30/82) for stool samples from Ariquemes, and 19.4% (26/134) for stool taken from the residents of Monte Negro. The rate of the occurrence of amoebiasis was significantly higher in the population from Ariquemes [p < 0.05; χ2 = 7.8; odds ratio = 2.4 (1.2 - 4.7)]. Due to the high occurrence of E. histolytica infected residents diagnosed in the region and the unavailability in local clinics of a test to distinguish between the two Entamoeba species, physicians should consider treating E. histolytica/E.dispar infections. The results indicate that E. histolytica infection is highly endemic in the studied areas.

Mykoserologie – sind wir weitergekommen? Aspergillus

Diseases caused by Aspergillus spp. are difficult to diagnose and thus require supplementary serological assays. This is the result of a selective review of the relevant literature with special regard to recent guidelines. In addition to conventional diagnostic tools (radiology, microscopy, culture) the measurement of the following serological markers is recommended, depending on the clinical type of aspergillosis: Invasive and chronic necrotising aspergillosis: Aspergillus-galactomannan antigen. Test format: EIA using the rat MAb EB-A2. Cut-off 0.5 (index). Monitoring of high risk patients: Twice weekly. Aspergillus-IgG (test format EIA) as confirmatory assay after recovery of the leukocyte function under therapy. Aspergilloma: Aspergillus IgG. Test format: EIA. Allergical aspergillosis: Aspergillus IgE. Test format: RAST. Galactomannan antigen detection rates high in the diagnosis of invasive aspergillosis. The evaluation of Aspergillus nucleic acid amplification assays is pending.

Current situation of Peste des petits ruminants (PPR) in the Sudan

The current situation of PPR in Sudan was investigated. A total of 61 tissue samples were collected from various PPR suspected outbreaks in sheep in Sudan during 2008. Collected tissue samples were tested for PPR antigen using IcELISA, PPR antigen was detected in 26 out of 61 samples (42.6%). Highest antigen detection rate was in specimens collected from western Sudan. A total of 1198 serum samples were collected from sheep (n = 500), camels (n = 392), and goats (n = 306) from different areas in Sudan (Khartoum, Gezira, Tambool, River Nile, Kordofan, White Nile, Blue Nile, Gedarif, Kassala, Halfa ElGadida, Port Sudan). Collected sera were examined for PPR antibodies using cELISA, a total of 336 (67.2%) sheep, 170 (55.6%) goat and 1 (0.3%) camel samples were found to be positive.

Chlamydophila spp. infection in horses with recurrent airway obstruction: similarities to human chronic obstructive disease

BackgroundRecurrent airway obstruction (RAO) in horses is a naturally occurring dust-induced disease mainly characterized by bronchiolitis which shows histological and pathophysiological similarities to human chronic obstructive pulmonary disease (COPD). In human COPD previous investigations indicated an association with Chlamydophila psittaci infection. The present study was designed (1) to clarify a possible role of this infectious agent in RAO and (2) to investigate the suitability of this equine disorder as a model for human COPD.MethodsClinico-pathological parameters of a total of 45 horses (25 horses with clinical signs of RAO and 20 clinically healthy controls) were compared to histological findings in lung tissue samples and infection by Chlamydiaceae using light microscopy, immunohistochemistry, and PCR.ResultsHorses with clinical signs of RAO vs. controls revealed more inflammatory changes in histology (p = 0.01), and a higher detection rate of Chlamydia psittaci antigens in all cells (p < 0.001) and bronchiolar epithelial cells alone (p < 0.001) by immunohistochemistry. The abundance of chlamydial inclusions increased with the severity of disease. PCR was positive in 60% of horses with RAO vs. 45% of the controls (p = 0.316). OmpA sequencing identified Chlamydophila psittaci (n = 9) and Chlamydophila abortus (n = 13) in both groups with no significant differences. Within the group of clinically healthy horses subgroups with no changes (n = 15) and slight inflammation of the small airways (n = 5) were identified. Also in the group of animals with RAO subgroups with slight (n = 16) and severe (n = 9) bronchiolitis could be formed. These four subgroups can be separated in parts by the number of cells positive for Chlamydia psittaci antigens.ConclusionChlamydophila psittaci or abortus were present in the lung of both clinically healthy horses and those with RAO. Immunohistochemistry revealed acute chlamydial infections with inflammation in RAO horses, whereas in clinically healthy animals mostly persistent chlamydial infection and no inflammatory reactions were seen. Stable dust as the known fundamental abiotic factor in RAO is comparable to smoking in human disease. These results show that RAO can be used as a model for human COPD.

Immunochemical identification and partial characterization of a native hepatitis C viral non-structural 4 antigen in sera of HCV infected patients

Background The identification of native HCV antigens may prove very useful in the diagnosis and early treatment of HCV infection. Here, we aimed to identify and partially characterize a native HCV-NS4 antigen. Methods The western blot, ELISA and immunohistochemical staining were used to identify the native antigen in sera and liver biopsies of HCV serotype 4 infected patients. Results The native NS4 antigen was identified in serum at 27-kDa molecular weight, in addition to a lower ∼ 21-kDa antigen. The purified HCV antigen showed a polypeptide band at 27-kDa when analyzed by silver stained SDS-PAGE and a single peak at 7.6 min by capillary zone electrophoresis. The immunostaining pattern of hepatocytes was cytoplasmic with mainly coarse granular and diffuse pattern based on specific rabbit antisera to the native HCV antigen. A highly significant correlation ( r = 0.797, p < 0.0001) was shown between serum concentrations of the HCV-NS4 antigen and HCV-RNA. Also, antigen detection rates were increased ( p < 0.05) with the progression of liver disease. Conclusion A native HCV-NS4 antigen was identified and partially characterized as 27-kDa protein and the NS4 antigenemia based ELISA test can serve as a useful addition to HCV diagnostic methods, especially under field condition.

Detection and Quantification of Pharaoh Ant Antigens in Household Dust Samples as Newly Identified Aeroallergens

Background:The widespread house ant, Monomorium pharaonis (pharaoh ant, PA), was recently identified as a potential cause of respiratory allergies. However, there are no reports of the distribution of PA allergens in various environments. We developed specific ELISA inhibition assays and measured the distribution and amount of PA antigens in household dust samples. Methods:Floor dust was collected at 3-month intervals from 56 homes in Seoul over a 1-year period. PA antigens in fine dusts were quantified by ELISA inhibition assays using rabbit anti-PA sera, and specific IgE to PA antigens in residents’ serum was measured by ELISA. Results: In 18 of the 56 homes (32.1%), PA antigen was detected in at least 1 floor dust sample either from the living room or the kitchen. Levels of PA antigens showed seasonal variations with peaks in autumn and winter. The detection rate of PA antigens was significantly higher in homes with visual evidence of PA infestations (70%) than in homes without such infestations (23.9%; p < 0.05). However, a significant amount of PA antigens was still detected in uninfested homes. Thirteen of 113 (11.5%) residents were positive for PA-specific IgE. PA-specific IgE was detected more frequently in residents living in PA antigen-positive homes (19.6%) than in antigen-negative homes (4.8%; p < 0.05). Conclusion: A considerable level of PA antigens is distributed in the indoor environment. Therefore, inhalant exposure to PA antigens can occur during domestic activities. These results suggest that PAs might be a significant source of aeroallergens in households.

Detection rate of Helicobacter pylori stool antigen in newborn infants and small children

To investigate the prevalence of H. pylori antigen in the stools of Norwegian neonates and small children. A total of 249 children aged 0 days-3 years were tested for the presence of H. pylori antigen in feces using the HpSA immunoassay. For verification purposes, a selection of samples were analyzed with PCR targeting the 16 S rDNA Helicobacter gene. H. pylori antigen in stool was detected in 52% (36/69) of the neonates, in 15% (7/46) of infants aged 7 days-1 month, and in 5% (7/134) of children aged 1 month-3 years. In neonates, H. pylori antigen detection was significantly associated with mode of delivery: 59% (30/51) with uncomplicated vaginal births were HpSA positive compared to only 10% (1/10) of infants delivered by cesarean section (P=0.02). Positive PCR results were found in 35% (9/26) of HpSA positive samples. Sequencing of PCR products revealed 97-100% homology with gene sequences from both H. pylori and other Helicobacter species. The low H. pylori antigen detection rate in children >1 month of age is in accordance with previous prevalence studies from Western countries. The unexpected finding of a high H. pylori antigen detection rate in neonates suggests that transient colonization may occur in the neonatal period.

Clinical, histological and immunohistochemical study of feline viral plaques and bowenoid in situ carcinomas

Feline viral plaques (FVP) induced by papillomavirus (PV) are often hyperpigmented and flat warts. The fact that up to 47% of bowenoid in situ carcinomas (BISC), which also usually occur in the form of hyperpigmented plaques, are positive for PV antigen in immunochemistry suggests that BISC could evolve from FVP. The relationship between the presence of PV antigens and the clinical and histological features of 26 cases of feline dermatoses (clinically described as pigmented plaques and with histological diagnosis of FVP and/or BISC) was therefore determined. The cases were classified into one of the three following groups: FVP, FVP + BISC or BISC. Immunohistological detection of papillomavirus group-specific antigen was performed using a polyclonal rabbit antibovine papillomavirus antiserum. Of the seven cases in the FVP group, six were deemed positive by immunohistology as were all 10 cats in the FVP + BISC group. On the other hand, only one of the nine BISC cats was positive. The presence of both FVP and BISC lesions in some cats and the high detection rate of PV antigens in the FVP and FVP + BISC groups suggest that both conditions might have the same viral cause and that some BISC may evolve from FVP. The low rate of viral antigen detection in the BISC group indicates another cause or a loss of viral replication during the cancerogenesis.

Co-agglutination test for cysticercus antigen detection in the serum for the diagnosis of cysticercosis

The objective of the study was to develop the co-agglutination (Co-A) test, a rapid slide agglutination test for the diagnosis of cysticercosis. The present study included 21 cases of cysticercosis, which comprised seven cases of clinico-radiologically definite cases of neurocysticercosis (NCC) proven with either computed tomography (CT) scan or magnetic resonance imaging (MRI), eight cases of clinically strong NCC, six cases of extraneural cysticercosis in muscle and eye; 40 non-cysticercal parasitic infection controls; and 20 healthy controls. Hyperimmune cysticercus antiserum was raised in rabbits and was used to coat Staphylococcus aureus (Cowan strain-I) bearing protein A (SAPA) cells, and the Co-A was standardized to detect cysticercal antigen in the serum. Serum samples from 12 out of 21 (57%) cases of cysticercosis were positive for cysticercal antigen by the Co-A test. Of the 12 positive samples, eight were from cases of neurocysticercosis and four from cases of extra-neural cysticercosis. Serum samples from seven out of 40 non-cysticercal parasitic infection controls and serum samples from one out of 20 (5%) healthy controls showed a false-positive reaction for the antigen by the Co-A test. There was a statistically significant difference between the antigen detection rates among cysticercosis patients on one hand, and the patients with other parasitic diseases (P = 0.0014), and healthy controls (P=0.0003) on the other. The Co-A test appears to be a moderately sensitive and specific test for the diagnosis of cysticercosis.