Histological and cellular evaluation of anterior cruciate ligament.

BACKGROUND: We hypothesized that the torn anterior cruciate ligament (ACL) demonstrates a great healing response after initial trauma and has competent cells leading to the healing but differs in its response based on the type of tear and duration of injury. This study aimed to evaluate the histological and cellular responses to the injured ACL. METHODS: Fifty-two tissue samples from the ACL were harvested from patients undergoing arthroscopy. Detailed histological and cellular examinations were performed for ligament angiogenesis, fibrocytes, and synovial tissue infiltration. We compared the cellular response to injury in partially and completely ruptured ACLs. The duration of ACL injury and its response to cellular characteristics were also examined. Immunohistochemical studies using cluster of differentiation 34 (CD34) staining was used to evaluate endothelial cells and fibrocytes. RESULTS: We found a significantly higher density of synovial and ligament angiogenesis and fibrocytes at the torn end of ACL (Mann-Whitney, P < 0.050). Numerous fibrocytes were identified in complete ACL tears versus partial tears (Mann-Whitney = 0.020). Increased cellular proliferation was identified at the ruptured end of ACL remnant (Kruskal-Wallis, P < 0.050). The cellular proliferation of ruptured ACL decreased after 12 months. CONCLUSIONS: Based on our findings of the time-dependent decrease in the cellular response at the torn ends of the ACL, we recommend early intervention, preservation of the ACL remnant, and primary ACL repair or augmented reconstruction.

Histopathological and microbiological findings and diagnostic performance of GeneXpert in clinically suspected tuberculous lymphadenitis.

OBJECTIVES: The primary objective was to determine the association between histopathological and microbiological findings in patients clinically suspected to have tuberculous lymphadenitis. A secondary objective was to assess the diagnostic utility of GeneXpert in lymph node specimens. METHOD: This was a single-centre prospective cohort study, performed in the Infectious Disease Clinic at The Indus Hospital. Three hundred and forty-one adult patients with chronically enlarged, accessible lymph nodes were enrolled after obtaining verbal consent, between February 2013 and April 2016. Tissue specimens were processed for histopathology, acid-fast bacillus (AFB) microscopy, AFB culture, and GeneXpert. Based on these results, anti-tuberculosis therapy (ATT) was prescribed. Clinical characteristics and treatment outcomes were recorded. RESULTS: There were 297 evaluable patients; 74.4% were diagnosed with tuberculous lymphadenitis (TBLA), 6.7% with a malignancy, and 12.8% with reactive nodes. TBLA was diagnosed on suggestive histopathology in 89.6% of cases, followed by GeneXpert (32.6%), mycobacterial culture (26.6%), and AFB smear positivity (12.5%). The sensitivity of GeneXpert was 65.7% when assessed against AFB culture. Drug resistance was displayed by 8.2% of GeneXpert-positive cases and 11.7% of culture-positive cases. The majority of TBLA patients (88.7%) responded favorably to ATT. CONCLUSIONS: In light of laboratory evidence, a quarter of patients suspected of TBLA had an alternative diagnosis, highlighting its importance in avoiding over-treatment and diagnostic delays in malignancy. Although sensitivity is poor, the demonstration of drug resistance by both GeneXpert and AFB culture represents a useful tool to guide treatment.