Chlamydia trachomatis: serological diagnosis

Chlamydial eye infections: Current perspectives

Chlamydia trachomatis, an obligate intraocular bacteria causing trachoma, adult and neonatal inclusion conjunctivitis, was the leading cause of blindness in the last century worldwide. Improvement in socioeconomic and living conditions, availability of antibiotics, and introduction of National Trachoma Control Programmes reduced the prevalence in developed countries, but it persisted in resource-poor settings of Africa and Asia, including India. In 2016, as per the WHO report, trachoma is restricted to 42 countries, causing blindness/visual impairment in ~1.9 million people. India is one of the five countries with nearly half of total active trachoma patients. Introduction of Global Elimination of Trachoma 2020 program by the WHO, using SAFE strategy (surgery for trachomatous trichiasis; Antibiotics for C. trachomatis; Facial cleanliness; and environmental improvement) greatly reduced the prevalence, but trachoma still persists in India. Global increase in the reproductive tract infection by C. trachomatis urogenital serotypes (D-K) has led to concurrent increase in C. trachomatis eye infections. Therefore, kerato eye infections due to chlamydial infections continue to be seen in hospitals. Over the years, there have been advances in laboratory diagnostics, in understanding the pathogenesis, tissue tropism, C. trachomatis genomics, and treatment modalities. Due attention and research is still needed for the study of C. trachomatis eye infections.

High frequency of latent Chlamydia trachomatis infection in patients with rhegmatogenous retinal detachment

AIM

To determine the frequency of detection of ocular and extraocular Chlamydia trachomatis (CT) infection in non-high myopes with rhegmatogenous retinal detachment (RRD).

METHODS

This was a single-center, nonrandomized, prospective, case-control study. One hundred and four patients were divided into a study group with RRD (n=63) and a control group with traumatic retinal detachment (n=41). Samples of subretinal fluid (SFR), conjunctival, urethral/cervical swabs, and blood were collected. The frequency of detection of CT infection in SRF samples was determined by polymerase chain reaction (PCR), direct fluorescence assay (DFA) and cell culture, whereas that in conjunctival swabs was determined by PCR and DFA, and those in urethral/cervical swabs and blood were determined by DFA. Yates Chi-square test (with Bonferroni correction) and two-tailed Student's t-test were used for statistical analysis.

RESULTS

SRF CT infection was detected more frequently in the study group (50.8%-71.4%) than in the control group (9.8%-12.2%) by all the methods used (P<0.01). The frequency of detection of conjunctival CT infection by DFA was higher in the RRD patients compared with the controls (81.0% vs 24.4%, P=0.004). The PCR detected conjunctival CT infection more often in the study group than in the controls (46.0% vs 9.8%, P=0.007). The DFA detected CT in blood specimens almost as frequently as in urogenital specimens, for the RRD patients (61.2% vs 63.5%) and the controls (7.3% vs 9.8%).

CONCLUSION

CT infection is detected with high frequency in non-high myopes with RRD.

Diffuse peritonitis and chronic ascites due to infection with Chlamydia trachomatis in patients without liver disease: new presentation of the Fitz-Hugh-Curtis syndrome

Two women were admitted for increasing abdominal pain, vaginal discharge, and severe or moderate chronic ascites. Diffuse peritonitis without evidence of liver disease was found in both cases, and in one the ascites and vaginal discharge contained Chlamydia trachomatis. Both patients responded to doxycycline, and this and the laboratory findings pointed strongly to C trachomatis as the aetiological agent. C trachomatis may cause severe peritoneal infections with chronic ascites formation in the absence of liver disease in women with the Fitz-Hugh-Curtis syndrome. Prompt diagnosis and antibiotics lead to rapid cure.

Perihepatitis (Fitz-Hugh--Curtis syndrome). A review and case presentation

Perihepatitis, or Fitz-Hugh--Curtis syndrome (FHC), is a complication of pelvic inflammatory disease (PID). Although though in the past Neisseria gonorrhoeae was thought to be the only etiological agent, recent data indicate that chlamydia trachomatis can produce the syndrome. Because cervical cultures frequently fail to demonstrate the presence of C. trachomatis, the serologic microimmunofluorescence antibody test is essential to diagnosis; the antibody titer in FHC syndrome is markedly higher than in PID without FHC syndrome. The classic presenting symptom of perihepatitis is severe right upper quadrant abdominal pain. If unnecessary diagnostic and surgical procedures are to be avoided, the FHC syndrome in the sexually active young woman must be included in the differential diagnosis of abdominal pain irrespective of its location. To illustrate the diagnosis and management of the FHC syndrome caused by C. trachomatis, a case of a 16-year-old adolescent female is presented.

Detection of experimental Chlamydia trachomatis eye infection in conjunctival smears and in tissue culture by use of fluorescein-conjugated monoclonal antibody

The immunofluorescent staining of conjunctival cytology smears with an antichlamydial monoclonal antibody is a new method for the detection of chlamydial eye infection. Using a monkey model of chlamydial eye infection, we compared the monoclonal antibody staining cytology with the established methods of Giemsa-stained cytology and chlamydial culture with cycloheximide-treated McCoy cells. Compared with either culture or monoclonal antibody-stained cytology, Giemsa cytology had a low sensitivity (30 and 24%, respectively) but was highly specific (100% in each case). Compared with culture, monoclonal antibody-stained cytology was highly sensitive (94%) but appeared to lack specificity (70%). However, examination of the changes in identification rates with time suggested that monoclonal antibody-stained cytology may be even more sensitive than culture and detect lower levels of infection. This study showed that monoclonal antibody-stained cytology of conjunctival smears might be a rapid, efficient, and inexpensive method of diagnosing ocular chlamydial infection.