Changes in collagen and elastic fiber contents of the skin, rectus sheath, transversalis fascia and peritoneum in primary inguinal hernia patients.

Background: It has been claimed that inguinal hernia is not a local disease; it is a local manifestation of a systemic disorder of collagen metabolism. Previous studies have shown that patients with inguinal hernia have some anomalies in collagen metabolism and changed ratio of collagen types.
Aim: To search the changes in collagen and elastic fiber contents of the skin, rectus sheath, transversalis fascia and peritoneum in primary inguinal hernia patients.
Methods and Materials: Twenty patients operated on for inguinal hernia (HR) included in the study (11 direct and 9 indirect). Nine patients underwent open cholecystectomy served as the control group (CC). A 0.5 x 1 cm. tissue was sampled from skin, rectus sheath, transversalis fascia and peritoneum in HR group. Skin, rectus sheath and peritoneum samples were taken from the patients in CC group. The sections of those samples were submitted to two different staining methods: "Masson's trichrome" for collagen and "van Gieson" for elastin fibers and graded with light microscopy.
Results: The rectus sheath samples of CC had higher staining scores for both collagen and elastin fibers in comparison with HR (p = 0.032 and p = 0.026, respectively). CC had a significantly higher score for collagen in peritoneum samples (p = 0.019). There were no statistically significant differences between the patients with direct and indirect inguinal hernias for collagen or elastin fibers scores in skin, rectus sheath, transversalis fascia and peritoneum samples.
Conclusions: These findings, which concur with most of the previous studies, support the theory that inguinal hernia may not be merely a local disease and can be more generalized, at least a regional connective tissue disorder. Regarding the difference between direct and indirect hernias, it could not be possible to report a certain answer, and this issue should be considered together with previous quantitative researches and more sophisticated studies may take place in the future (Tab. 2, Fig. 2, Ref. 23).