*5.3.8 Corticosteroids*

Anti-inflammatory steroids are known to inhibit cell development. Additionally, they are known to decrease inflammatory response. Macrophage response to chemotactic signals as well as phagocytosis by polymorphonuclear neutrophils and

macrophages is negatively affected by the stabilising impact of steroids on lysosomes. Epithelialisation, which is a critical step in wound healing is inhibited by glucocorticoids such as hydrocorticosterone [57].

Things are further complicated by the low-secretory state induced by corticosteroids due to their effect on the endoplasmic reticulum. Thus, risk of wound dehiscence is consequently enhanced due to the reduced deposition of collagen [58].

#### **5.4 Genetic syndromes associated with abnormal wound healing**

#### *5.4.1 Cutis laxa*

Defective elastin fibres as evidenced in cutis laxa- an acquired or congenital disorder, impacts wound healing. Characterised by skin that is loose (lax), wrinkled, sagging, and lacking elasticity (inelastic). The inelastic skin returns to place abnormally slowly when stretched. The skin around the face, arms and legs etc. are the predominantly affected parts and give patients a prematurely-aged appearance [59].

#### *5.4.2 Ehlers-Danlos Syndrome*

Characterised by deficit in collagen metabolism, it is a group of connective tissue abnormalities that lead to defects in the inherent strength, elasticity, integrity, and healing properties of the tissues [60, 61]. Even mild injury in Ehlers-Danlos patients may lead to severe bruising and the development of wide, 'open' wounds due to the delayed healing [27, 60, 61].

#### *5.4.3 Osteogenesis imperfecta*

An inheritable disorder of connective tissue, clinical features of this condition include bone fragility, neonatal dwarfism, deformities of the long bones, scoliosis, ligamentous laxity, blue sclerae, defective dentinogenesis, and deafness. While there are four major forms, mutations in the genes that encode type I collagen is a common trait that result in the formation of wide scars [27, 62].
