Macroscopic Agglutination Test Research Articles

Epidemiological characterization of Leptospira spp. infection in working horses and in an occupationally exposed population in six Colombian police stations

Introduction: Police working horses are in close contact with their managers and the general population during recreational and patrol activities, which can favor the transmission of leptospirosis among the horses and the occupationally exposed personnel. Objective. To characterize epidemiologically leptospirosis through serology, urine culture and PCR in working horses and in the occupationally exposed population in six police stations in Colombia. Materials and methods. We tested 153 castrated male horses and 123 people in six police stations in the municipalities of Manizales, Pereira, Armenia, Ibagué, Tuluá, and Cali. Three structured formats were applied and blood samples were obtained from people and horses, which were processed with the Macroscopic Agglutination Test, (MAT) for 24 serogroups. Horses were subject to a clinical examination, and urine samples were obtained for urine culture and conventional PCR. Results. The seroprevalence of human Leptospira spp. was 3.25% (n=4) while in horses it was 85% (n=130). Among the horses, serogroups Djasiman and Shermani were the most prevalent. The urine culture was positive in 64.7% (99/153) of the samples, whereas PCR analyzes were negative. A statistically significant association was found between the frequency of exiting the facilities (p=0.009) and the presence of wildlife (p=0.0051) with the infection by serogroup Shermani. Conclusion. The epidemiological characteristics of leptospirosis in horses suggest an endemic presentation of the infection and its role as reservoirs of the bacteria; however, it is necessary to elucidate the pathogenesis of the disease with complementary studies.

Efficacy of a New Recrystallized Enrofloxacin Hydrochloride-Dihydrate against Leptospirosis in a Hamster Model.

A trial on Syrian hamsters (Mesocricetus auratus) infected with Leptospira interrogans serovar Canicola was established to compare treatment efficacies of daily intramuscular (i.m.) injections of either 10 mg/kg of 5% enrofloxacin (Baytril [BE]; Bayer Animal Health, Mexico) or the same dose of enrofloxacin hydrochloride-dihydrate (enro-C). Hamsters were experimentally infected via the oral submucosa with 400 microorganisms/animal, in a sequential time schedule aligned to the initial treatment day, and were treated in groups as follows: a group treated with 5% enrofloxacin daily for 7 days after 24 h of infection (group BE24); a group treated as described for group BE24 but with enro-C (enro-C24); a group also treated with 5% enrofloxacin but starting at 72 h after infection (BE74); a group treated as described for group BE74 but with injection of enro-C (enro-C74). An untreated-uninfected control group (group CG-) and an infected-untreated control group (group CG+) were assembled (n = 18 in all groups). Weights and temperatures of the hamsters were monitored daily for 28 days. After hamsters were euthanatized or following death, necropsy, histopathology, macroscopic agglutination tests (MAT), bacterial culture, and PCR were performed. The mortality rates were 38.8% in group BE24 and 100% in group BE74 No mortality was observed in group enro-C24, and 11.1% mortality was recorded in group enro-C74 The mortality rates in groups CG+ and CG- were 100% and zero, respectively. Combined necropsy and histopathologic findings revealed signs of septicemia and organ damage in groups BE24, BE72, and CG+ Groups enro-C24 and CG- showed no lesions. Moderated lesions were registered in 3 hamsters in group enro-C72 MAT results were positive in 83.3% of BE24 hamsters (83.3%) and 100% of BE72 and CG+ hamsters; MAT results were positive in 16.7% in group Enro-C24 and 38.9% in group enro-C72 Only 4/18 were PCR positive in group enro-C72 and only 1 in group enro-C24 (P < 0.05). It can be concluded that enro-C may be a viable option to treat leptospirosis in hamsters and that this may be the case in other species.

English

Leptospirosis is a zoonosis of global distribution caused by infection with pathogenic spirochaetes of the genus Leptospira. Humans are accidental hosts and usually become infected through contact with water or soil contaminated by the urine of infected animals such as rodents, dogs, cattle and pigs. In developing countries such as India, leptospirosis is often underdiagnosed because of its protean clinical manifestations leading to significant morbidity and mortality. It occurs as a self-limited illness in 85% to 90% of the cases and icteric leptospirosis or Weil's syndrome, a more serious, potentially fatal syndrome which occurs in 5% to 10% of the cases. Microbiological diagnosis of leptospirosis aims at demonstrating the leptospires, by culturing them or by demonstrating an appreciable antibody response to them. A definite diagnosis of leptospirosis is based either on isolation of the organism from the patient or on seroconversion or a rise in antibody titre in the MAT. Leptospires may be visualized in clinical material by DGM or by IF or light microscopy after appropriate staining. The sensitivity of blood cultures is low; hence culture is primarily used for retrospective diagnosis. There are numerous serological tests available for diagnosis of leptospirosis like Macroscopic agglutination test (MSAT), Indirect fluorescent antibody test (IFAT), Sensitised erythrocyte lysis test (SEL), Complement fixation test (CFT), Enzyme Linked Sorbent Assay (ELISA), Microcapsule agglutination test (MCAT), Lepto-Dipstick, Latex agglutination test, Dried Latex agglutination test (Lepto Tek Dri-Dot), but they are only genus specific. To identify the specific serovar Microscopic agglutination test (MAT) or culture has to be done. The various available options for a diagnosis of leptospirosis have been explored in this article. A thorough literary search was done in the various published data available- pub med search was done as well as

Diagnóstico de leptospirosis humana: evaluación de la aglutinación macroscópica en diferentes etapas de la enfermedad

To evaluate the macroscopic agglutination test using Temperature Resistant (TR) antigen as a screening test for the diagnosis of human leptospirosis in different stages of the disease. The criteria for case definition were based on the results of the microscopic agglutination test (MAT), leukocyte counts and neutrophilia, resulting 218 confirmed cases and 242 non- cases. Each sample was classified according to the days of the disease progression in three stages: first (<10 days), second (10 - 25 days) and third (> 25 days). The design was cross-sectional observational. TR sensitivity was 71,1% on stage 1. 93.4% on stage 2 and 95.6% on stage 3. The specificity at different stages ranged from 79.0 to 69.2%. Intra and inter-operator variability was moderate. TR variability, low sensitivity in the first stage and low specificity found in all stages of the disease, suggest that it is essential to incorporate new diagnostic methods to screen for early detection of cases in our country and in countries that still apply such methods.

Acute kidney injury in the tropics

Acute kidney injury (AKI) is one of the most challenging problems faced by clinicians in the tropics owing to its fast-changing burden. AKI in the tropics is strikingly different from that in the developed world in terms of etiology and presentation. In addition, there is a stark contrast between well-developed and poor areas in the tropics. The true epidemiological picture of AKI in the tropics is not well understood due to the late presentation of patients to tertiary centers. Infections remain the major culprit in most cases of AKI, with high mortality rates in the tropics. Human immunodeficiency virus–related AKI, related to nephrotoxicity due to antiretroviral therapy, is on the rise. Acute tubular necrosis and thrombotic microangiopathy are the most common mechanisms of AKI. A notable problem in the tropics is the scarcity of resources in health centers to support patients who require critical care due to AKI. This article reviews the unique and contrasting nature of AKI in the tropics and describes its management in each situation.

Leptospirosis: a problem for transfusion medicine?

Leptospirosis is underdiagnosed owing to its non-specific presentation, especially in the early stages of the infection. In the present research, sera from 2368 healthy blood donors of a local blood bank were screened for the presence of leptospiral antibodies using IgM-Pk-ELISA, followed by the microscopic and macroscopic agglutination tests. Serum samples showing two positive and/or borderline results in these assays were confirmed by immunoblotting. The IgM-antibody profile was defined according to the following criteria: sera reactive to a diffuse band of molecular weight 14.8-22 kDa were considered leptospirosis positive, sera exhibiting no reactivity to this band were considered negative. Our results showed a prevalence of 1.01% positivity. There is evidence that transmission of Leptospira interrogans by blood transfusion is possible, but, to date there has been no documentation of transfusion-transmitted leptospirosis. Thus, according to the currently available information, there is no need for new bloodbanking procedures to identify possible carriers of L. interrogans.

A card test for the serodiagnosis of human leptospirosis.

A macroscopic agglutination test for detecting leptospiral antibodies in human sera is described. The test utilizes a stained preparation of non-pathogenic leptospires and is performed on the Brewer diagnostic cards used for bovine brucellosis screening. The agglutination of the stained antigen is more easily observed than the current macroscopic slide test using unstained leptospiral antigens. The non-pathogenic serotype patoc is agglutinated by sera from humans infected with serotypes pomona, hardjo, ballum, and copenhageni with a sensitivity of 94% in comparison with the microscopic agglutination test.

Evaluation of a Hemagglutination Test for Human Leptospirosis

An indirect hemagglutination test for the diagnosis of leptospirosis is described; the test uses a soluble antigen from serotype patoc to sensitize sheep erythrocytes which are then fixed with glutaraldehyde. Evaluation of this procedure indicates that it is more reliable than the conventional macroscopic agglutination test and, in contrast with both microscopic and macroscopic agglutination tests, is positive only with sera from persons with current leptospiral illness. The test is simple and convenient and sensitized fixed cells may be stored for at least a year. In comparison with the macroscopic and microscopic tests, only a single antigen is required.

Species differences in platelet agglutination in man and in the dog, swine and rabbit.

The in vitro agglutination of platelets by incubated plasma-cation mixtures was studied in man and in the dog, swine and rabbit. A macroscopic agglutination test previously described was used. In homologous tests TAg activity was demonstrated in swine and in the dog. TAg is a thrombocyte agglutinating factor not adsorbed by BaSO4 and active with Mg++ and Mn++. In all species agglutination also occurred with Ca++ and whole plasma; in the dog and in man this activity was removed from plasma by BaSO4 adsorption, and in the dog was recovered in the eluate. This agglutinating factor is tentatively designated TAg'. In the rabbit and in swine, platelets were agglutinated with adsorbed plasma and Ca++ From studies with heterologous mixtures of plasma and platelets, it was concluded that the platelet rather than the plasma determines species differences in cation requirements and agglutinability. All plasmas studied cause platelet agglutination characteristic of the platelet species if appropriate cations are present. Porcine plasma appears to contain a heterophil antibody for human platelets.

A simple screening test for the detection of leptospirosis in human beings and animals.

DRINCIPLES of a simple agglutination test for rheumatoid arthritis, using sensitized latex particles that were described by Singer and Plotz,12 were applied to a macroscopic agglutination test for evidence of leptospirosis. Latexleptospiral suspensions were found to form stable, readily recognizable aggregates in the presence of leptospiral antibodies. The procedure is easily performed. The test requires only 90 minutes' incubation and the results are easily read with the naked eye. This report describes the technic of the test and presents an evaluation of sensitivity based on the examination of human and animal sera.

Advances in Knowledge of Poultry Diseases Over the Past Fifty Years

ABSTRACT INTRODUCTION MOST of what we know about poultry diseases has been learned in the past fifty years. By now, the pertinent literature is voluminous. A review article of reasonable length, that is supposed to cover these fifty years of very productive research and learning, can do no more than touch upon the most significant advances, made in that period. BACTERIAL DISEASES Pullorum Disease. Advances of great scientific and economic importance were the discoveries of the cause (Rettger, 1900) and mode of transmission (Rettger and Stoneburn, 1909) of pullorum disease. This was the first time a bacterial disease had been proved to be egg-borne. The importance of the application of the macroscopic agglutination test to the detection of carriers of Salmonella pullorum (Jones, 1913b; Gage et al., 1914; Rettger et al., 1914) is well known to all concerned with poultry husbandry and control of disease. Important contributions toward the control and . . .

Methods for the Detection of Antibodies against Mammalian Spermatozoa: I. A Modified Macroscopic Agglutination Test

Methods for the Detection of Antibodies against Mammalian Spermatozoa: I. A Modified Macroscopic Agglutination Test

Comparison of a Recently Developed Macroscopic Agglutination Test for the Diagnosis of Leptospiral Jaundice with the Standard Microscopic Test

The laboratory diagnosis of leptospiral jaundice has been handicapped by the lack of a simple serological test. Satisfactory microscopic agglutination tests have been described, among others, by Schiiffner and Mochtar,1 Erber,2 and Fletcher.3 While these tests are quite satisfactory, they have the decided disadvantage that they require microscopic examination by dark ground illumination, and are relatively time-consuming to perform. Pot4 and Smith and Tulloch5 have described macroscopic agglutination tests in which formalized cul-

A Macroscopic Agglutination Test with Typhus Rickettsiae Prepared from Infected Rodent Lungs

ployed agglutination of rickettsiae to measure the result of immunizing the horse against typhus, and FitzPatrick4 showed that agglutinins appeared in monkeys and guinea pigs after vaccination with agar slant-tissue cultures of rickettsiae of typhus and spotted fever, respectively. The presence of rickettsial agglutinins in the serum of typhus vaccinated persons was studied by Liu, Zia and Wang,5 and after experimental typhus infection by Zia and Liu.6 The antigens used in the agglutination tests reported have been the Weigl louse vaccine,1,2,3,5 peritoneal washings of infected rats,,2 and chick tissue culture on agar slants.4 A difficulty militating against the exstensive use of the test in research and in diagnosis of human typhus has been the lack of rickettsiae in large enough numbers and in a sufficiently purified state. More recent advances in the cultivation of rickettsiae

Production of an Antipertussis Serum of High Titer

During some investigations on the relative susceptibility of various laboratory animals to the toxemia resulting from the injection of Bacillus pertussis, it was discovered that birds were to all intents and purposes entirely immune to the toxic effects of this organism. It seemed reasonable to assume, therefore, that birds would be admirably suited to the production of an immune serum of high potency, and that, perhaps, this immune serum would possess certain therapeutic effects on the disease as it occurs in man. Accordingly, preliminary work, with the pigeon as the host, was done, the details of which need not be discussed. Suffice it to say that the results obtained with the pigeon as the host warranted the production of serum in larger quantities. Accordingly, twelve full grown Australorpe cocks were purchased and tested for infection with Salmonella pullorum by a macroscopic agglutination test, six strains of S. pullorum from three different sources being used as the antigen. Only birds that were shown to be uninfected were used.

The Occurrence of White Diarrhea Infection in Eggs Laid by Hens Reacting to the Agglutination test

One of the problems being investigated at this laboratory is the affects of White Diarrhea infection upon mature hens, their eggs and their offspring. A part of this problem involves a bacteriological study, with special reference to Salmonella pullora (Bacterium pullorum), of eggs laid by hens reacting to the serum agglutination test which is employed for detecting birds that harbor or have harbored the microorganisms causing this disease. This paper presents the results obtained this spring upon examining the eggs laid by 14 reacting White Leghorn hens which belonged to a flock of high producing birds. Considerable work has been done on this phase of the problem by other workers, notably, Rettger and Stoneburn1–2, Rettger, Kirkpatrick and Stoneburn3, Rettger4, Jones5, Gage, Paige, Hyland6, Rettger7, Hadley and Caldwell8 and May9.SOURCE OF THE HENS FURNISHING EGGSFifteen White Leghorn hens, which had recently reacted to the macroscopic agglutination test for .

A Plea for the Standardization of Reports of Agglutination Tests

Abstract Possibly the time has not yet arrived when it is desirable to standardize the methods employed in making the macroscopic agglutination test, although there is an increasing tendency upon the part of bacteriologists to employ the technique presented by Kolmer (1915) in which the dilutions of the serum to be tested start at 1:20 and proceed by doubling to give 1/40 1/80, 1/160, 1/320, etc. But in the manner in which tests are reported for publication there is observable a great discrepancy on the part of different authors. For the sake of comparative work it would seem to be of advantage to possess a standardized method of reporting these results, whatever the technique of making the tests may have been. A review of published results of agglutination tests indicates readily enough that the plus sign (+), for indicating a positive test, and the minus sign (-) or a zero (0), for indicating a negative result, have been commonly adopted.