A 47-year-old woman presented with a pustular rash (Figure and ) on her skin (face, back, forearms and leg) and pustular inguinal eruptions; on one occasion she had developed a vulvar infection with abscess formation requiring drainage. Past medical history included recurrent rhinosinusitis and anxiety disorder. Biopsy of the lesion showed pustular changes with neutrophilic infiltration, but did not reveal lymphocyte infiltration. A culture from a lesion on her forearm was positive for Staphylococcus aureus. The patient responded to administration of cefadroxil and minocycline, with remission and frequent relapses. Laboratory workup revealed mild C4 deficiency and an undetectable IgE level (Table ). Assays were unremarkable for ANA, ESR, rheumatoid factor, hepatitis viruses, and HIV. The MBL level was exceptionally low at < 50 ng/ml, and her MBL functional pathway was impaired. MBL genotyping revealed a LYPB/HYPD haplotype, while MASP-2 was wild-type (Table ).
A 48-year-old woman presented with painful orogenital ulcerations. She had a family history of documented Behcet's disease (BD) in her father and brother and she was concerned she may have the disease. She was uncertain as to whether she was of Melungeon descent (peoples of Tri-racial descent who have lived in the South-Eastern United States: these include European, African/Middle Eastern/Turkish and Native American). Pertinent other history included severe polyarthralgia (hands, wrists, arms, knees, and ankles) over the past 8 years.\nA pathergy test was negative. Immunoglobulin levels, ESR, and CRP were unremarkable. Assays for hepatitis viruses, HIV, rheumatoid factor, Herpes simplex, and lupus anticoagulant were negative (Table ). Ophthalmologic evaluation did not demonstrate the characteristic uveitis. She was treated with a pulse of oral glucocorticoids and placed on long term hydroxychloroquin. After 5 months, oral and genital ulcerations had resolved. Due to the clinical response to therapy but insufficient diagnostic criteria, she was diagnosed with a forme fruste of BD. Further work-up established an MBL level < 50 ng/ml and a deficient MBL functional pathway (Table ). Genotyping revealed an LXPA/LYPB haplotype for MBL and A/A for MASP-2 (Table ).