To the Editor:
Patients with concurrent neurofibromatosis type 1 (NF-1) and systemic lupus erythematosus (SLE) rarely have been reported in the literature. Neurofibromatosis type 1 is one of the most common genetic disorders, with a worldwide birth incidence of 1 in 2500 individuals and prevalence of 1 in 4000 individuals.1 The incidence and prevalence of SLE varies widely depending on race and geographic location. Estimated incidence rates for SLE range from 1 to 25 per 100,000 individuals annually in North America, South America, Europe, and Asia.2,3 The reported worldwide prevalence is 20 to 150 cases per 100,000 individuals annually.2,4,5
Given the high prevalence of both conditions, the association between SLE and NF-1 likely is underrecognized; therefore, identifying more patients with concurrent SLE and NF-1 and describing the interplay between the 2 conditions may have important therapeutic implications. We present the case of a middle-aged woman with a history of SLE who had cutaneous lesions characteristic of NF-1 to further the understanding of these concurrent conditions.
A middle-aged woman presented to our academic dermatology clinic for evaluation and removal of dark spots that had been present diffusely on the trunk and extremities since birth. She reported a history of SLE with lupus nephritis, hypertension, and a nodular goiter following a partial thyroidectomy. She noted that she did not seek treatment for the skin findings sooner because she was more concerned about her other medical conditions; however, because she felt these conditions were now stable, she decided to seek treatment for the “rash.” Physical examination revealed hundreds of café au lait macules and numerous neurofibromas diffusely distributed on the trunk and extremities (Figure 1) as well as bilateral axillary freckling. A clinical diagnosis of NF-1 was made.
Figure 1. Café au lait macules and neurofibromas on the upper back.
When questioned, the patient reported that she may have been diagnosed with NF-1 in the past by another physician, but she did not recall it specifically. The patient was advised that there were no treatments for the café au lait macules. We notified her other physicians of the NF-1 diagnosis so she could be monitored for systemic conditions related to NF-1, including optic gliomas, pheochromocytoma, renal artery stenosis, and internal neurofibromas. We also referred the patient for genetic counseling; of note, the patient reported she had 4 children without any evidence of similar skin lesions or chronic health problems.