Keratomalacia with Descemetocele in a 2.5-month-old boy (Grand Rounds)

From EyeWiki
Original article contributed by: Mohammad H. Dastjerdi, MD
All contributors: Maria A. Woodward, MD
Assigned editor:
Review: Assigned status Not reviewed by Priti Batta, MD on February 17, 2017.


Keratomalacia with Descemetocele in a 2.5-month-old boy (Grand Rounds)

Chief Complaint

A 2.5-month-old Caucasian boy was referred from outside hospital for concern of perforated corneal ulcer in the right eye.

History

History of Present Illness

  • Patient's mother states that her son has had mucus discharge in both eyes since a month ago.
  • She was told by his pediatrician that the baby has tear duct obstruction.
  • Patient was treated with Neosporin ophthalmic ointment which was stopped 4 days later because the eyelids became red and swollen.
  • Two days ago, she noticed a white spot on the right eye that she tried to clean it off thinking it was mucus, but she was unable to remove it; therefore, she presented to a local eye doctor and was then immediately referred to Children's Mercy Hospital for further evaluation and treatment.

Review of Systems

  • Diaper rash.
  • Loose stools for the last 2 weeks


Medical History

Past Medical History

  • Born full term after an uncomplicated pregnancy.
  • At birth, short stay in the NICU for 4-5 days due to low levels of oxygen, temperature instability, and low blood glucose.
  • The mother was carrier for group B streptococcus.
  • Immunizations is up to date.


Family History

  • Parents and 3 siblings are healthy.
  • A maternal uncle in his 30s, who has had multiple respiratory infections.
  • A maternal aunt who died at 8 days of life.
  • Mother and his 2 sisters have eczema.
  • There are cataracts in grandparents but no other eye diseases.


Allergies

  • No Known Allergies

Medìcations

  • Mylicon as needed for gas.


Social History

  • The patient lives at home with his mother, father, and 3 siblings.
  • He is not exposed to daycare.
  • Mother states they have good access to care and Medicaid for the kids, denies any insecurity obtained food, housing, or basic needs for the family.


Examination

Vision

  • OD: not able to fix and follow
  • OS: fixing and following light

Pupils

  • OD: not visible
  • OS: miotic
  • Unable to evaluate for APD


External Exam

  • Eyelids and periorbital area without edema, erythema, or lesion
  • Eyelids well apposed to the globe with no laxity or conjunctival/corneal exposure


Images

  • Examination under anesthesia (EUA)
  • See the pictures

MHDSlide14.JPG MHDSlide15.JPG MHDSlide16.JPG

EUA findings:

  • Severe conjunctival xerosis in both eyes.
  • The right cornea with a large paracentral opacity and ulceration with about 4x5 mm Seidel positive descemetocele.
  • Anterior chamber was shallow and iris was adherent to the area of descemetocele
  • Dilated Fundus Exam
    • No view OD
    • Normal disk, macula, vessels, and periphery

Differential Diagnosis

  • Vitamin A deficiency
  • Infectious keratitis
  • Exposure keratopathy
  • Severe dry eye
  • Hereditary sensory and autonomic dysfunction syndromes (Riley—Day syndrome)


Initial Work-up and Treatment

  • Corneal scrapings were performed for microbiology.
  • Cyanoacrylate tissue adhesive with a bandage contact lens was applied to the right cornea.
  • Treatment was started with hourly fortified vancomycin (50 mg/mL) and tobramycin (14 mg/mL) eye drops.
  • Patient was admitted to the hospital for further workup.

MHDSlide20.JPG MHDSlide21.JPG

Laboratory Testing

  • Serum vitamin A: <2mcg/dL (normal range:20-43)
  • Sweat chloride test 127 mmol/ml (normal range: 0-29 mmol/ml)
  • Corneal cultures grew no organism
  • Molecular genetics: Two cystic fibrosis transmembrane conductance regulator (CFTR) gene mutations; 1078deIT mutation and R1158X mutation.

Final Diagnosis

  • Vitamin A deficiency associated with cystic fibrosis

Vitamin A Deficiency

Epidemiology

  • Is one of four leading causes of preventable blindness (the other 3: cataract, trachoma, and onchocerciasis).
  • Is the leading cause of preventable blindness in children.
  • Is responsible for at least 20,000-100,000 new cases of blindness worldwide each year.
  • Is a public health problem in more than half of all countries, especially in Africa and South-East Asia.

Etiology and Pathogenesis

  • Vitamin A is an essential fat-soluble vitamin which is vital for ocular metabolism:
    • Maintenance of the conjunctival and corneal epithelial surfaces
    • Maintenance of retinal phototransduction and retinal pigment epithelial viability
  • This vitamin must be acquired through either:
    • Animal-derived products
    • Vitamin A precursors known as carotenoids found in leafy green and yellow vegetables
    • Synthetic vitamin A analogs known as retinoids
  • The mechanisms of vitamin A deficiency include:
    • Malnutrition
    • Malabsorptive conditions
    • Disorders that impair vitamin A metabolism or storage such as alcoholism or other chronic liver diseases
  • The deficiency is rarely seen in developed western hemisphere:
    • Celiac sprue
    • Cystic fibrosis
    • Chronic alcoholism and cirrhosis
    • Self-imposed dietary practices
    • After bowel resection and bariatric surgeries

Ocular Signs and Symptoms

  • Night blindness
  • Xeropthalmia
  • Keratomalacia
Classification of ocular manifestations by the WHO
XN Night blindness
XIA Conjunctival xerosis
XIB Bitot’s spots
X2 Corneal xerosis
X3A Corneal ulceration/keratomalacia < 1/3 of corneal surface
X3B Corneal ulceration/keratomalacia > 1/3 of corneal surface
XS Corneal scar
XF Xerophthalmic fundus
  • Night blindness (nyctalopia) is the most common and earliest symptom of vitamin A deficiency:
    • Inadequate regeneration of rhodopsin
    • Retinal function does not always correlate with anterior segment findings.
  • Prolonged vitamin A deficiency leads to xerosis(dryness of the conjunctiva and cornea):
    • Loss of goblet cells
    • Tear film instability
    • Squamous metaplasia and keratinization ocular surfaces
    • Corneal ulcers and scars
    • Diffuse corneal necrosis (keratomalacia)
  • Bitot's spots are foamy gray, triangular spots of focal keratinized epithelium on the conjunctiva
  • Histologically, Bitot's spots are tangles of keratin admixed with gas-forming saprophytic organisms (often corynebacterium xerosis) which is likely responsible for the its typical "foamy" appearance.

MHDSlide34.JPG

  • Keratomalacia (in severe cases) presents as a corneal ulceration destructing the epithelium, which releasing collagenase and can cause rapid stromal liquifactive necrosis, descematocele and perforation.
  • Xerophthalmic fundus, a rare associated abnormality, features yellow-white spots in the peripheral retina.
  • Xerophthalmic fundus is largely a clinical oddity and does not necessarily correlate to severity of disease.

Differential Diagnosis

  • Ocular surface diseases such as cicatricial pem phigoid, Stevens-Johnson syndrome, atopic keratoconjunctivitis, radiation and chemical injury can lead to squamous metaplasia of the ocular surface epithelia.

Cystic Fibrosis

  • Cystic fibrosis (CF) is an autosomal recessive disease with hyperviscosity of mucus secretions causing chronic pulmonary changes and pancreatic insufficiency.
  • CF causes fat malabsorption resulting in fa-soluble vitamin deficiency.
  • Ocular findings of CF include:
    • Xerophthalmia
    • Tear film abnormalities
    • Papilledema (increased ICP)
    • Nyctalopia
    • Keratomalacia
  • Infants with CF who develop vitamin A deficiency can demonstrate bulging fontanels (increased ICP) and failure to thrive before ocular signs.
  • Advanced xerophthalmia has been reported as an initial sign of CF.
  • However, keratomalacia is very rarely seen in children less than two years of age.


Treatment

  • The diagnosis of xerophthalmia constitutes a medical emergency, and immediate vitamin A replacement is important for the restoration of the ocular surface.
  • WHO standard doses vary with the age of the patient:
    • In children >12 months of age 200 000 lU immediately and again the following day. An additional dose should be given 2 weeks later to boost liver reserves.
    • For children aged 6 to 12 months, half dosage is recommended.
    • For children < 6 months of age, quarter dosage is recommended.
  • In patients with malabsorptive conditions parenteral (intramuscular) replacement with water-miscible retinol palmitate is essential.
  • Dramatic response of xerophthalmia after therapy with vitamin A and initiation of a cystic fibrosis regimen.
  • Fortified topical antibiotics were tapered.
  • Cyanoacrylate glue came off after two weeks.
  • Corneal ulcer healed with a small area of residual scar, thinning, and vascularization.

MHDSlide45.JPG MHDSlide46.JPG MHDSlide47.JPG

Comments

  • This report indicates that advanced xerophthalmia, keratomalacia, and descemetocele may be the first presenting signs in cystic fibrosis.
  • This report indicates that keratomalacia associated with vitamin A deficiency can occur as early as 2-month of age.
  • This case illustrates the importance of immediate treatment with vitamin A to improve xerosis, help resolving keratomalacia, and promote complete reepithelialization.
  • Also, this case illustrates that immediate corneal grafting may not be indicated in keratomalacia and descemetocele in setting of vitamin A deficiency given the challenges of pediatric keratoplasty.

Discussion

Please use the discussion tab at the top of this page to talk about this case.

Contact

Mohammad H Dastjerdi, MD Department of Ophthalmology University of Kansas

References

  1. Reddy V. History of the International Vitamin A Consultative Group 1975-2000. J Nutr. 2002; 132:2852S-6S.
  2. Lee V. Extent of vitamin A deficiency among rural pregnant women in Bangladesh. Public Health Nutr. 2008;11:1326-31.
  3. Sommer A. Xerophthalmia, keratomalacia, and nutritional blindness. Int Ophthalmol . 1990; 14:195—199.
  4. Vitamín A deficiency and xerophthalmia. Report of a Joint WHO/USAID Meeting. World Health Organ Tech Rep Ser. 1976;590:1—88.
  5. Lindenmuth K. Advanced xerophthalmia as a presenting sign in cystic fibrosis. Ann Ophthalmol. 1989;21:189-191.
  6. Brooks H. Xerophthalmia and cystic fibrosis. Arch Ophthalmol. 1990;108:354-357.