Local and systemic expressions of MMP-9, TIMP-1 and PAI-1 in patients undergoing surgery for clinically suspected appendicitis

Individual biomarkers in the blood are not yet applicable in diagnosing complicated appendicitis: A scoping review

BACKGROUND

Appendicitis is one of the most common surgical emergencies globally and it can both be difficult to diagnose but also to differentiate complicated from uncomplicated appendicitis preoperatively. The objective of this scoping review was to develop an overview of biomarkers in blood discriminating complicated from uncomplicated appendicitis and characterize their applicability in an acute setting including time, cost, and analysis technique required as well as their individual precision.

METHOD

This scoping review was reported in accordance with PRISMA-ScR. The included studies had to report on biomarkers measured in the blood for at least ten patients with suspected appendicitis. A systematic literature search was conducted on August 28, 2022, in PubMed and Embase but restricted to articles published in January 2000 and onwards. A protocol was uploaded to Open Science Framework prior to data extraction.

RESULTS

A total of 65 biomarkers were included from 52 studies, covering 14,312 patients. There was 60% routine- and 40% novel biomarkers based on the reported analysis technique. The most frequently investigated biomarkers within each group were white blood cell count and procalcitonin. The routine biomarkers were of low financial cost but poor diagnostic accuracy with sensitivity ranging between 15 and 100% and specificity between 27 and 100%. Novel markers were costly ranging from 275 to 800$, and their diagnostic accuracy was based on limited population sizes (median 34 patients) and reported for only 5% of the novel markers.

CONCLUSION

Routine biomarkers were applicable in an acute setting but had poor diagnostic accuracy. Novel biomarkers are being investigated for potential, but the concept is still premature due to lack of diagnostic accuracy studies reporting cost-benefit for individual markers and whether they can be applied in an acute setting.

Clinical, Morphological, and Immunohistochemical Justification of Surgery for Chronic Appendicitis in Children

Objective: Chronic appendicitis (CA) is a diagnosis characterized by long-standing right lower quadrant pain. We analyzed clinical, morphological, and immunohistochemical studies of the appendix to confirm the adequacy of surgery for CA in children with chronic right lower quadrant pain. Patients and Methods: We carried out comparative studies of clinical presentations and results of morphological and immunohistochemical studies of remote appendicitis in 55 children with chronic recurrent lower quadrant pain (CRLQP). Results: Morphological and immunohistochemical studies revealed three types of changes in the appendix. Type 1 (n = 21)-chronic inflammation. Inflammatory leukocyte infiltration was localized within the mucous membrane of the appendix. An immunohistochemical study revealed a significant (P < .01) increase in the expression of CD106 (vascular cell adhesion molecule 1) and in the number of matrix metalloproteinase 9 (MMP-9) positive cells. Type 2 (n = 20)-lymphoid hyperplasia. Morphological changes were characterized by lymphoid infiltration of the mucosa and submucosa of the appendix. Immunological changes were characterized by an increase (P < .01) in the expression and number of MMP-9, expression of CD106 positive cells, an increase in the expression of collagen IIIα in combination with a decrease in the expression and number of positive vascular endothelial growth factor (VEGF) and vasoactive intestinal peptide cells. Type 3 (n = 12)-catarrhal inflammation. Morphological changes were characterized by impaired blood circulation only in the mucous membrane, without destructive or inflammatory changes. Immunological changes were characterized by an increase (P < .01) in the expression and number of VEGF-positive cells, which may indicate a response to local hypoxia of the appendix and explain neovascularization in a chronic condition. The abdominal syndrome after appendectomy was noted to disappear in 89% of patients. The established changes in remote appendicitis, other than acute inflammation, make it possible to consider reasonable appendectomy a way of treating CRLQP in children. Conclusions: We have identified immunohistochemical and morphological changes pointing to autoimmune and vascular mechanisms of appendix damage in children with CRLQP. Laparoscopic appendectomy helps to eliminate abdominal pain in most CA patients.

Roles of TGF-β/Smad signaling pathway in pathogenesis and development of gluteal muscle contracture

PURPOSE OF THE STUDY

Gluteal muscle contracture (GMC) is a chronic fibrotic disease of gluteal muscles which is characterized by excessive deposition of collagen in the extracellular matrix. Transforming growth factor (TGF)-βs have been shown to play an important role in the progression of GMC. However, the underlying mechanisms are not entirely clear. We sought to explore the expression of TGF-β/Smad pathway proteins and their downstream targets in gluteal muscle contracture disease.

MATERIALS AND METHODS

The expression levels of collagens type I/III, TGF-β1, Smad2/3/4/7 and PAI-1 (plasminogen activator inhibitor type 1) in gluteal muscle contraction (GMC) patients were measured using immunohistochemistry, reverse transcription and polymerase chain reaction (RT-PCR) and western blot assays.

RESULTS

The expressions of collagens type I/III and TGF-β1 were significantly increased in the contraction band compared with unaffected muscle. In addition, R-Smad phosphorylation and Smad4 protein expression in the contraction band were also elevated, while the expression of Smad7 was significantly decreased in the fibrotic muscle of the GMC patients compared to the unaffected adjacent muscle. The protein and mRNA levels of PAI-1 were also remarkably increased in the contraction band compared with adjacent muscle. Immunohistochemical analysis also demonstrated that the expression levels of TGF-β1 and PAI-1 were higher in contraction band than those in the adjacent muscle.

CONCLUSION

Our data confirm the stimulating effects of the TGF-β/Smad pathway in gluteal muscle contracture disease and reveal the internal changes of TGF-β/Smad pathway proteins and their corresponding targets in gluteal muscle contracture patients.