Introduction
For the first time in 1969, Rosai and Dorfman described a new
clinicopathologic entity of histiocytic proliferative disorders, which
they named sinus histiocytosis with massive lymphadenopathy (SHML)1. SHML, also known as the Rosai-Dorfman disease
(RDD), is a non-Langerhans cell histiocytosis disorder with unknown
etiology that is histologically characterized by benign proliferation of
S100–positive histiocytes within the expanded sinus of lymph nodes and
lymphatic vessels of visceral organs 2. This rare
disease mainly affects children and younger adults but can also occur as
late as the eighth decade 3. Evidence suggests that
patients with a background of immunologic and autoimmune diseases are
more susceptible to developing this disease 4, 5.
Patients with RDD most commonly present with massive and bilateral
painless enlargement of cervical lymph nodes, accompanied by
non-specific symptoms such as fever, night sweat and weight loss. In
approximately 40% of cases, RDD can also display extranodal involvement
with the most common affected sites being the bone, skin, soft tissue,
and upper respiratory tract 6. RDD is usually
self-limited and has an overall good prognosis; however, the extranodal
involvement of vital organs, as well as the presence of immunological
disorders is associated with unfavorable outcomes and might require
therapeutic interventions such as surgery or medical treatment5, 7.
Kidney involvement occurs in an estimated four percent of patients with
extranodal RDD and is associated with a poor prognosis6. Thus far, only two cases of isolated bilateral
renal RDD have been reported, which had both been symptomatic at
presentation 8, 9. Here, we report the third case of
isolated bilateral renal RDD in a 67-year-old asymptomatic woman who
presented with an elevated erythrocyte sedimentation rate (ESR) and
increased serum creatinine level. In addition, we briefly review the
radiologic findings of previously reported cases of renal RDD and
compare them with other differential diagnoses.