Leukocyte adhesion deficiency type III in an infant presenting with intestinal perforation and low percentage of natural killer cells: first case report from Iran.

Background: Leukocyte adhesion deficiency III (LAD III) is a very rare autosomal recessive primary immunodeficiency characterized by recurrent infections without pus formation and bleeding syndrome of Glanzmann-type and life-threatening infections. The main etiology of this condition is variations in the FERMT3 gene, which encodes kindlin-3, an integrin-binding protein. We present a toddler with unique symptom of intestinal perforation followed by prolonged bleeding due to Glanzmann-like thrombasthenia who was diagnosed as LAD-III.

Case presentation: This report presents a toddler with leukocyte adhesion deficiency type III (LAD III), who was diagnosed because of protracted surgical wound and gastrointestinal bleeding following surgery for small bowel perforation at the age of 16 months. The patient's history was positive for febrile episodes after vaccinations, recurrent pulmonary infections, frequent severe epistaxis and ecchymotic purpuric lesions since early infancy. The presence of severe bleeding symptoms encouraged us to consider LAD III. Accordingly, sanger sequencing was performed which identified that the patient was homozygote for mutation in exon 14 of FERMT3 gene, the gene encoding for kindlin-3. Our patient also showed low percentages of CD16 and CD56 on peripheral blood flow cytometry, an unheard finding in LAD type III.

Conclusions: LAD III should be considered in differential diagnosis of any child with recurrent infections, persistent leukocytosis, and bleeding disorders. This is the first case of LAD III presenting with intestinal perforation. The present case also showed low percentage of natural killer cells which should be followed in further studies.