Category: Uncategorized

MUCOUS MEMBRANE GRAFTING: THE QUIZ

1. Which of the following statements is true about Steven Johnson Syndrome (SJS)?

1. Caused by a type IV hypersensitivity reaction
2. SJS leads to detachment of > 30% of skin over the entire body surface area
3. Both a and b
4. None of the above

2.  What are the possible ocular features of SJS?

1. Destruction of limbal stem cells
2. Lid margin keratinisation
3. Corneal ulceration
4. All of the above

3. Which of the following does not cause SJS?

1. Mycoplasma Pneumoniae
2. Anticonvulsant therapy
3. Systemic antibiotics
4. All of the above can cause SJS

4. Which of the following is true about ocular involvement in SJS?

1. Incidence may be as high as 50%
2. Amniotic membrane grafting can be performed in early stages
3. Mucous membrane grafting is the preferred procedure for treating lid margin keratinisation
4. In bilateral end stage disease, keratoprosthesis may be an effective alternative for visual rehabilitation
5. All of the above

5. What are the possible indications for mucous membrane grafting in Ophthalmology?

1. Lid margin keratinisation in SJS
2. Refractory vernal keratoconjunctivitis
3. None of the above
4. Both a and b

ANSWERS:

1. a. Caused by a type IV hypersensitivity reaction.

Stevens-Johnson Syndrome (SJS) and toxic epidermal necrolysis (TEN) are severe cutaneous adverse reactions (SCAR) that belong to type IV hypersensitivity, mediated by immunological effect.

SJS and TEN differ in the extent of detached or detachable skin. SJS affects <10% of the body surface area with, SJS/TEN overlap affects 10%-30% of the body surface and TEN affects >30%.

Liotti L, Caimmi S, Bottau P, et al. Clinical features, outcomes and treatment in children with drug induced Stevens-Johnson syndrome and toxic epidermal necrolysis. Acta Biomed. 2019;90(3-S):52‐60.

DOI: 10.23750/abm.v90i3-S.8165

Types of Hypersensitivity reactions are as follows:

2. d. All of the above

Corneal complications include epithelial defect, infiltration, and ulceration and are reported in 18%– 20% of cases. The lid margin changes occurring include meibomian gland metaplasia, trichiasis, punctal scarring, and lid margin keratinization.

Destruction of limbal stem cells results in replacement of corneal epithelium by conjunctival epithelium. This destruction to limbal stem cells is ongoing in SJS because of persistent inflammation. The preexisting primary damage to the limbal stem cells determines the further course of the disease—either squamous metaplasia or conjunctivalization.

Iyer G, Pillai VS, Srinivasan B, et al. Mucous membrane grafting for lid margin keratinization in Stevens–Johnson syndrome: results. Cornea. 2010 Feb;29(2):146-51

DOI: 10.1097/ICO.0b013e3181ae2691

3. d. All of the above can cause SJS. Kim et al in a study of 82 patients attributed the occurrence of SJS- TEN to the following agents