Human homozygous type I plasminogen deficiency and ligneous conjunctivitis
A M Mingers1, A Philapitsch, P Zeitler
1Children's Hospital of the University of Würzburg, Germany.
Summary
Severe plasminogen deficiency, a rare genetic condition, was identified in 10 patients with ligneous conjunctivitis. This deficiency, particularly type I, affects mucous membranes and is not linked to thrombosis.
Area of Science:
- Ophthalmology
- Hematology
- Genetics
Background:
- Ligneous conjunctivitis and pseudomembranous disease are rare conditions.
- Plasminogen deficiency is a known risk factor for thrombosis, but its role in mucous membrane diseases is less understood.
Purpose of the Study:
- To investigate the role of plasminogen deficiency in patients with ligneous conjunctivitis or pseudomembranous disease.
- To characterize the genetic basis and clinical manifestations of plasminogen deficiency in affected individuals.
Main Methods:
- Questionnaire survey of German hospital ophthalmology departments.
- Genetic analysis for plasminogen deficiency (homozygous and heterozygous).
- Measurement of polymorphonuclear (PMN)-elastase, factor XII, C1-inhibitor, prekallikrein, and plasminogen activator inhibitor type 1 (PAI-1).
- Monitoring of fibrinolytic activity markers (D-dimer, plasmin-antiplasmin complex) following lys-plasminogen concentrate infusions.
Main Results:
- Ten patients with ligneous conjunctivitis/pseudomembranous disease and severely reduced plasminogen levels were identified.
- Homozygous type I plasminogen deficiency was found in 7 patients, a previously undescribed form in humans.
- Elevated PMN-elastase, factor XII deficiency, and alterations in C1-inhibitor, prekallikrein, and PAI-1 were observed.
- Lys-plasminogen infusions normalized fibrinolytic markers and other measured parameters, suggesting efficacy.
Conclusions:
- Severe type I plasminogen deficiency, distinct from dysplasminogenemia, primarily affects extravascular spaces like mucous membranes.
- This deficiency may be triggered by vascular lesions in the context of ligneous conjunctivitis.
- Plasminogen replacement therapy shows promise in managing fibrinolytic defects associated with this condition.
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