Hemophagocytic lymphohistiocytosis (HLH), also known as haemophagocytic lymphohistiocytosis (British spelling), and hemophagocytic or haemophagocytic syndrome, is an uncommon hematologic disorder seen more often in children than in adults. It is a life-threatening disease of severe hyperinflammation caused by uncontrolled proliferation of activated lymphocytes and macrophages, characterised by proliferation of morphologically benign lymphocytes and macrophages that secrete high amounts of inflammatory cytokines. It is classified as one of the cytokine storm syndromes. There are inherited and non-inherited (acquired) causes of hemophagocytic lymphohistiocytosis (HLH). Signs and symptoms
The onset of HLH occurs before the age of one year in approximately 70 percent of cases. Familial HLH should be suspected if siblings are diagnosed with HLH or if symptoms recur when therapy has been stopped. Familial HLH is an autosomal recessive disease, hence each sibling of a child with familial HLH has a twenty-five–percent chance of developing the disease, a fifty-percent chance of carrying the defective gene (which is very rarely associated with any risk of disease), and a twenty-five–percent chance of not being affected and not carrying the gene defect.Patients with HLH, especially when untreated, may need intensive therapy. Therefore, HLH should be included in the differential diagnosis of intensive care unit patients with cytopenia and hyperferritinemia. Patients in the earlier stages of HLH are frequently hospitalized at internal medicine wards.HLH clinically manifests with fever, enlargement of the liver and spleen, enlarged lymph nodes, yellow discoloration of the skin and eyes, and a rash.
Nummular keratitis is a feature of viral keratoconjunctivitis. It is a common feature of adenoviral keratoconjunctivitis (an ocular adenovirus infection), as well as approximately 1/3rd of cases of Herpes Zoster Ophthalmicus infections. It represents the presence of anterior stromal infiltrates. Unilateral or bilateral subepithelial lesions of the cornea may be present. Slit lamp examination reveals multiple tiny granular deposits surrounded by a halo of stromal haze. After healing, residual nummular scars often remain. Disciform keratitis occurs in 50% of individuals with Nummular keratitis, but Nummular keratitis always precedes Disciform keratitis. Treatment
Lubricating eye drops
Topical dilute steroid drops in tapering doses (debatable, see: Adenoviral keratoconjunctivitis)


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