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rdd ( rosai dorfman disease ) , also called shml ( sinus histiocytosis with massive lymphadenopathy ) , was first described by rosai and dorfman in 1969 1 .
rdd is a rare and self - limiting disorder that more frequently affects children , adolescents , and young men ; however , it can occur in adults and the elderly 2 .
its main clinical manifestation is painless cervical lymph node involvement , but other lymph nodes can also be involved .
involvement in extranodal sites , such as the skin , brain , pericardium , scrotum , bone , eyes , upper respiratory tract , breast , heart , thyroid , etc . have also been described 28 . in a recent study ,
purely extranodal rdd cases were reported to occur more commonly than purely nodal cases ( 77% vs. 8) 9 .
some viruses , such as ebv ( epstein  barr virus ) and human herpes virus 6 ( hhv6 ) , have been , suggested to be the causative agents of rdd , but concrete evidence is still lacking 10,11 .
few rdd cases that were associated with hiv infection have been described in the literature . here ,
we report cytologic findings after fna ( fine needle aspiration ) in a patient with rdd and hiv infection .
a man infected with type 1 hiv sought consultation for cervical swelling that had rapidly evolved over 4  months .
he also complained of night sweats , but had no history of fever or weight loss .
physical examination revealed swollen cervical lymph nodes with diameters of up to 3  cm that were firm , painless , and bilateral , but not symmetrical .
the blood count results were as follows : hemoglobin = 10.2  g / dl , mcv = 84 fl , wbc = 7.8  g / l , platelet count = 189  g / l , neutrophil count=3.8 
a cervical lymph node sample obtained by fna and stained with mgg revealed the following findings ( fig.1 ) : ( a ) ( 10 ) histiocytes throughout the smear .
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 low power examination ( 10 , 40 ) : presence of diffusely distributed histiocytes throughout the smears with vacuolated cytoplasm ( fig.1a , b ) 
 
 high power examination ( 100 ) : histiocytes with single , double , or multiple nuclei , fine chromatin and prominent basophilic nucleoli , abundant cytoplasm containing several intact plasma cells or lymphocytes , defined as emperipolesis ( fig.1c , d ) , and an occasional halo around the phagocytized cells ( fig.1e ) . these cytological confirmed rdd . 
 
histology ( fig.2 ) provided a definitive diagnosis of rdd with emperipolesis ( fig.2a ) , and immunohistochemical staining revealed positivity for s-100 protein and cd 68 ( fig.2b , c ) .
( a ) hematoxylin eosine staining ( 20 ) revealed sinuses filled with numerous histiocytes containing viable cells in their cytoplasm ( emperipolesis ) .
this asymptomatic patient has been diagnosed with hiv - positive 10  months prior to attending our clinic , with a cd4 cell count of 610 cells/l and a viral load of 150,000 copies of rna/l . at the time of rdd diagnosis ,
the chest radiograph , and the computed tomography scan of the thorax and abdomen were normal .
he had no signs of vital organ compression or airway obstruction , so his condition was monitored ( he did not receive any treatment ) and re - examined at 4 and 6  weeks after the diagnosis .
the size of the patient 's lymph nodes had not significantly increased at those follow - up examinations , and he was subsequently lost to follow - up .
rosai dorfman disease was first described in 1969 , and it is a rare nonmalignant histiocytic disorder that affects all age groups , including pediatric and elderly patients 5,6 .
relationships between rdd and hhv6 , epstein  barr virus , klebsiella , and cytomegalovirus have been suggested , but attempts to isolate those organisms in patients diagnosed with rdd have consistently failed 1012 . to date
rdd is very rarely associated with hiv infection , with < 10 cases having been reported to date . to the best of our knowledge
, this case is the eighth to be reported . a summary of the sites of involvement , cytological features , histological features , and the treatments / courses of rdd cases with such an association are presented in table1 
 1318 .
rosai dorfman disease associated with hiv infection m , male ; f , female ; hiv , human immunodeficiency virus ; hhv-6 , human herpes virus 6 ; hsv , herpes simplex virus ; ebv , epstien - barr virus ; vzv , virus varicella zona ; cmv , cytomegalo virus ; sts , serological tests for syphilis .
the main clinical manifestation of rdd is massive , bilateral , and painless cervical adenopathy , and extranodal disease is common .
the sites of involvement in order of frequency are the cervical , axillary , inguinal , para - aortic , and mediastinal lymph nodes .
extranodal manifestation of the disease is observed in 2843% of patients , with the head and neck region being the most common site affected 20 .
the most common clinical presentation of the eight reported cases of rdd associated with hiv ( 75% ) was the mixed form ( nodal and extranodal involvement ) .
the diagnosis of rdd can be difficult , as the patient may not have the classic features associated with nodal disease , such as fever , leukocytosis , and elevated esr .
our patient did not have fever and had a wbc = 7.8g / l and an esr = 32  mm / h .
lymphadenopathy cases with and without hiv infection are caused by hodgkin disease , lymphoma , metastatic carcinoma , langerhan 's cells histiocytosis , chronic infection etc .
if the lesions or lymphadenopathy persist , fine - needle aspiration or tissue biopsy is indicated .
the cytological features of rdd include the presence of intact lymphocytes , specifically , histiocytes containing plasma cells and a single nucleus or multiple nuclei of different sizes and shapes , inconspicuous to prominent nucleoli ,  and an abundantly pale cytoplasm .
it differs from phagocytosis in that the cells that are taken up in the lesion are not attacked by enzymes and remain intact within the cytoplasm .
immunohistochemical features include positivity for s100 protein and cd68 , and negativity for cd1a 13,15,17,19 .
these cytologic and histologic findings , which were found in our patient , are characteristic of rdd and essentially present in all rdd cases , regardless of the sites of involvement ( nodal or extranodal ) and regardless of the type of infection or associated pathology . to date
surgery is performed for symptomatic cases , including cases with airway compression , vital organ compression , or cosmetic issues especially in cutaneous rdd cases .
other treatment modalities , such as chemotherapy , corticosteroids , and radiotherapy , have been performed with variable results 12,15,16,19 . in patients with rdd and hiv infection , different treatment modalities
number 5 ( table1 ) died and that patient was an infant with cmv eod ( end - organ disease ) complicated by bone marrow failure 17 .
based on the currently available data , we do not believe , that patients with asymptomatic hiv infection are more vulnerable to developing rdd .
however , more studies must be undertaken to determine the role of hiv in the pathogenesis and/or its course of rdd .
our case was followed for 6  weeks after diagnosis , and the size of the patient 's lymph node remained stable .
rosai dorfman disease is a very rare , benign , self - limiting histioproliferative disorder .
its cytologic features are so distinctive that it can be easily diagnosed by fnac ( fine - needle aspiration cytology ) , which is minimally invasive
. if the lesions are accessible by fine needle aspiration , a biopsy may not be necessary .
rosai dorfman disease has rarely been described to be associated with hiv , and it is not known whether hiv infection contributes to the development of an environment that stimulates macrophage activation .
key clinical messagerdd ( rosai dorfman disease ) is a rare and benign histiocytic proliferative disorder of unknown etiology . 
 fnac ( fine - needle aspiration cytology ) is a useful and reliable tool for the diagnosis of rdd , and as such , biopsy is avoidable .