For centuries, keloids have been a well known clinical problem and despite considerable research to unravel this phenomenon there is still no universally accepted or effective treatment. Keloids and hypertrophic scars occur worldwide in all skin types but they are more common in people of African descent. Incidence rates of 16% among adult Africans have been reported while these percentages were considerably lower among schoolchildren.In severe forms they can become disabling.
Etiology and pathogenesis
Hypertrophic scars and keloids are formed from excessive scar tissue formation at the site of prior skin injury. There is often a familial tendency for developing hypertrophic scars and keloids but the pathogenesis remains unknown. Most probably nutritional, biochemical, immunological, and genetic factors play a role in the abnormal wound healing. Another hypothesis is the influence of change in hormonal status. This might be the reason that in children before puberty there is no keloid formation after piercing the earlobes. Unfortunately prevention is often not successful.
Keloids are fibrous tumors caused by overgrowth of connective tissue. They occur as a result of skin injury, such as burns, surgical or tribal cuts and ear piercing but also after inflammatory skin diseases like acne and herpes zoster. Sites of predilection are shoulders, upper back, chest and earlobes. At first lesions are pink-to purple and often pruritic and painful. Hypertrophic scarring is restricted to the area of the original lesion and has a tendency of gradual resolution over time. Keloids can migrate into adjacent tissue to form hard, irregular shiny ridges or plaques and are persistent. 
- Differentiating between a hypertrophic scar and keloid can be difficult.
- Kaposi sarcoma
- Keloids and hypertrophic scars are chronic skin conditions, their treatment also takes time!
- One of the most important things that one can do to prevent the formation of keloids is to avoid trauma to the skin, attend to cuts or abrasions immediately to minimize inflammation and infection, avoid ear piercing and refrain from elective surgery unless medically indicated
- Intralesional steroid injections: eg kenacort (1:40) on a 1:1 dilution with lidocain 2% once every 3 weeks.
- The following treatments should be preferably carried out in a specialized or university hospital:
- Surgical excision of keloids leads to recurrence and more deformity. In severe cases debulking may be needed, and should be followed by regular intralesional steroid injections.
- Cryosurgery in combination with intralesional corticosteroids can be used for small lesions.
- Pressure with silastic gel sheets or pressure garments at night for several months.
- Radiotherapy is highly successful but the use is limited due to its damaging long term side effects
- ↑ 1.0 1.1 Louw L. Keloids in rural black South Africans. Part 1: general overview and essential fatty acid hypotheses for keloid formation and prevention. Prostaglandins Leukot Essent Fatty Acids 2000; 63: 237-45.
- ↑ Alhady SM, Sivanantharajah K. Keloids in various races. A review of 175 cases. Plast Reconstr Surg 1969; 44: 564-6.
- ↑ Hogewoning AA, et al. Skindiseases among schoolchildren in Ghana, Gabon and Rwanda. August 2012 ; accepted for publication in the International Journal of Dermatology.
- ↑ 4.0 4.1 Gauglitz GG, Korting HC, Pavicic T et al. Hypertrophic scarring and keloids: pathomechanisms and current and emerging treatment strategies. Mol Med 2011; 17: 113-25.
- ↑ Louw L, Dannhauser A. Keloids in rural black South Africans. Part 2: dietary fatty acid intake and total phospholipid fatty acid profile in the blood of keloid patients. Prostaglandins Leukot Essent Fatty Acids 2000; 63: 247-53.
- ↑ Al-Attar A, Mess S, Thomassen JM et al. Keloid pathogenesis and treatment. Plast Reconstr Surg 2006; 117: 286-300.
- ↑ Berman B, Flores F. Recurrence rates of excised keloids treated with postoperative triamcinolone acetonide injections or interferon alfa-2b injections. J Am Acad Dermatol 1997; 37: 755-7.