Discussion
Rosai-Dorfman disease (RDD), also known as sinus histiocytosis with
massive lymphadenopathy, a rare disease with a variable presentation and
course. Specific incidence and prevalence is not known for this disease
with only about 1000 reported cases worldwide.(5) It
is common in males than in females 4:1 and it affects all age groups but
more frequently reported in young children and adolescents especially in
the first two or three decades. Its pathogenesis remains unknown, though
there is no clear causative agent in most cases, a link between human
herpes virus 6 (HHV-6), Epstein-Barr virus (EBV) and parvovirus B19 has
been suggested, though not conclusive (4)
The clinical presentation of RDD has several predictable signs and
symptoms, the most common nodal site being painless bilateral cervical
lymphadenopathy reported in nearly 90% of cases.(1),(4)
Extra- nodal involvement is observed in approximately 40% of cases and
can occur anywhere in the body with the most common sites including the
skin, gastrointestinal tract, eyes, external and internal ear, skeletal
system, upper and lower respiratory tracts, oral cavity, nasal and
paranasal cavities, and the central nervous system(1),(3),(6),(7) CNS involvement is rare, and the
constitutional symptoms are absent, this poses a therapeutic challenge
as spontaneous remission is rare and there is no standard therapeutic
protocol for its treatment. From a case series of 6 patients with CNS
involvement all underwent surgical excision, followed by chemotherapy
and steroids. (7)
Our case was a young female who presented fevers and multiple cervical,
sublingual, submandibular and supra clavicular lymphadenopathy, with
leukocytosis, neutrophilia, anemia, thrombocytosis, an elevated C- RP
and ESR. However, the possibility of Rosai-Dorfman disease was not
considered clinically till FNAC cytology reports were available. In our
setting this presentation can easily be misdiagnosed as it mimics common
infections like TB adenitis and malignancy like lymphoma. The
differentials include reactive lymphadenitis, tuberculosis, lymphoma,
metastatic carcinoma, hemophagocytic syndrome, and Gaucher’s disease.
Our patient was initially diagnosed as TB adenitis and kept on Anti TB
medication for 1 month without any resolution of symptom’s . Due to its
rare occurrence this poses a diagnostic challenge. We screened her for
viral etiology like EBV, CMV and herpes virus which have been linked to
the etiology of this disease, the results were negative.
Our patient was diagnosed using FNAC, When compared to surgical core or
excisional biopsy, FNAC can at times be misinterpreted due to limited or
non-representative sampling and, as it does not permit examination of
the tissue architecture, diagnosis can be further confounded.
Despite these limitations, FNAC is still a very useful tool for the
diagnosis of RDD. (8),(9),(10)
Histology findings include alteration of the normal lymph node
architecture by massive sinusoidal dilation that contains histiocytes,
lymphocytes, and plasma cells. Emperipolesis within the histiocyte
cytoplasm is the classical finding in RDD. The histiocytes will be
positive for immunohistochemical stains CD68 and S100 and are typically
negative for CD1a.
There is no unified therapeutic protocol for the treatment of this
disease, spontaneous remission is observed, therefore “ wait and
watch” approach is recommended. (4)
Our patient was treated with steroids at a dose of 10mg twice daily per
day (2mg/kg) for 2 weeks and then taper off over 4 weeks. She was
asymptomatic after 3 weeks of starting the treatment. Surgery remains
the mainstay treatment for RDD. For symptomatic patients requiring
systemic therapy steroids are first-line therapeutic option that
produces responses in both nodal and extra-nodal disease; however, the
reliability and durability of these responses is unpredictable,
furthermore the duration of treatment is also not known. Very limited
clinical trials have been done using chemotherapy and radiotherapy
therefore the effectiveness of these methods is still uncertain. In
cases of disseminated disease chemotherapy has been used with agents
such as vinca-alkaloids, anthracyclines, and alkylating agents with
varying response rates. Radiotherapy is considered a palliative method
in patients with symptomatic disease. (2) (4)
RDD has been postulated to remit and relapse, however the recurrence
rate is unknown. We are following up our patient every 3 monthly for at
least 2 years to assess for the possibility of future relapse.
The parents of this child were losing hope in the beginning, as they
could not see any difference in their child’s symptoms despite of all
the medication and investigations that were taken. But later once she
was on steroids and after thorough counselling them, they were very
co-operative and appreciated our efforts to help their child.