Detección de Chlamydia spp. en leucocitos de sangre periférica de ovinos sin aborto previo / Detection of Chlamydia spp. In Peripheral Blood Leukocytes in Ewes without any Previous Abortion

Resumen El aborto enzootico ovino es una enfermedad causada por Chlamydia abortus. Es considerada una zoonosis y una de las principales causas de pérdidas económicas en estas explotaciones. Este trabajo se enfocó en utilizar el cultivo de leucocitos de animales sin signos de abortos y la detección de anticuerpos para determinar la posible presencia de C. abortus en explotaciones de traspatio. Se obtuvieron 42 muestras de sangre periférica de ovejas de diferentes poblaciones. La detección de Chlamydia abortus se realizó mediante la tinción de Giemsa y la técnica de PCR. La detección de anticuerpos anti-C. abortus se dio mediante una técnica de ELISA comercial. Los resultados mostraron 21 muestras positivas mediante la técnica de PCR, de las cuales solo 10 fueron positivas mediante la técnica de Giemsa, mientras que 22 sueros mostraron anticuerpos anti-C. abortus. En este estudio el 38,1 % de las muestras fueron positivas a la infección por C. abortus, como se confirmó mediante PCR y serología. En conclusión, los leucocitos de sangre periférica pueden ser útiles para detectar una infección por Chlamydia spp. en explotaciones sin historial de abortos, con lo que se puede conocer la prevalencia real del aborto enzootico ovino en México.

Abstract The Ewes Enzootic Abortion is a disease caused byChlamydia abortus. It is deemed a zoonosis and one of the leading causes of financial losses in this type of business. This article focuses on using the culture of leukocytes from animals without any abortion symptoms and antibody detection to determine the potential presence ofC. abortusin backyard exploitations. Forty-two samples of peripheral blood were obtained from ewes in different populations. The detection ofChlamydia abortuswas carried out by using the Giemsa dye and PCR technique. Anti-C. Abortusantibody detection was performed through a commercial ELISA technique. Results showed 21 positive samples using the PCR, and only ten were positive according to the Giemsa dye, while 22 serum samples showed anti-C. abortusantibody. In this study, 38.1% of the samples were positive for theC. abortusinfection, as verified with the PCR and serology. In conclusion, peripheral blood leukocytes can be helpful to detect an infection caused byChlamydiaspp. Animal exploitation without any previous abortion allows knowing the real prevalence of ewes' enzootic abortion in Mexico.

Non-biofilm-forming commensal Staphylococcus epidermidis isolates produce biofilm in the presence of trypsin.

Epidemiological studies comparing clinical and commensal Staphylococcus epidermidis isolates suggest that biofilm formation is a discriminant biomarker. A study showed that four non-biofilm-forming clinical S. epidermidis isolates could form an induced biofilm by trypsin treatment, suggesting that S. epidermidis can form biofilms in a protease-independent way and in a trypsin-induced way. In this study, the trypsin capacity to induce biofilm formation was evaluated in non-biofilm-forming S. epidermidis isolates (n = 133) in order to support this mechanism and to establish the importance of total biofilms (meaning the sum of protease-independent biofilm and trypsin-induced biofilm). Staphylococcus epidermidis isolates from ocular infections (OI; n = 24), prosthetic joint infections (PJI; n = 64), and healthy skin (HS-1; n = 100) were screened for protease-independent biofilm formation according to Christensen's method. The result was that there are significant differences (p < .0001) between clinical (43.2%) and commensal (17%) protease-independent biofilm producers. Meanwhile, non-biofilm-forming isolates were treated with trypsin, and biofilm formation was evaluated by the same method. The number of commensal trypsin-induced biofilm producers significantly increased from 17% to 79%. In contrast, clinical isolates increased from 43.2% to 72.7%. The comparison between clinical and commensal total biofilm yielded no significant differences (p = .392). A similar result was found when different isolation sources were compared (OI vs. HS-1 and PJI vs. HS-1). The genotype icaA- /aap+ was associated with the trypsin-induced biofilm phenotype; however, no correlation was observed between aap mRNA expression and the level of trypsin-induced biofilm phenotype. Studying another group of commensal S. epidermidis non-biofilm-forming isolates (HS-2; n = 139) from different body sites, it was found that 70 isolates (60.3%) formed trypsin-induced biofilms. In conclusion, trypsin is capable of inducing biofilm production in non-biofilm-forming commensal S. epidermidis isolates with the icaA- /aap+ genotype, and there is no significant difference in total biofilms when comparing clinical and commensal isolates, suggesting that total biofilms are not a discriminant biomarker.

Eosinophilia in Preterm Born Infants Infected with Chlamydia trachomatis.

A higher than 350 eosinophils/mm(3) is strongly associated with Chlamydia trachomatis in term born babies coursing with respiratory distress. However, in preterm newborns infected with this pathogen, the levels of eosinophils are unknown. Forty newborn infants with clinical data of respiratory problems and/or sepsis were analyzed. DNA of leukocytes from peripheral blood was used to identify C. trachomatis. Detection of chlamydial infection was performed by amplifying the ompA gene by an in-house PCR, and eosinophil levels were evaluated in an XT-2000-hematology analyzer. Eighteen infants showed chlamydial infection and 14 of them showed pneumonia (RR = 2.6; CI95% 1.03-6.5; p =.027). Their eosinophil levels were 719 ± 614 cells/mm(3). A significant association between eosinophilia ≥1250 cells/mm(3) and gestational age of less than 29 weeks (RR = 5.8; 1.35; CI95% [1.4-24.5], p <.008) was observed. The preterm infants with chlamydial infection did not show higher eosinophil levels than uninfected infants.