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xanthogranulomas are benign , usually asymptomatic , self - healing , red , yellow , or brown papules , nodules composed of histiocytic cells that predominantly occur in infancy and childhood .
adamson first reported juvenile xanthogranuloma ( jxg ) in 1905 . but during 1912 , mcdonough reviewed the condition and renamed it as nevoxanthoendothelioma . in 1954 , helwig and hackney re - termed it as jxg , reflecting its histopathological appearance .
it belongs to a heterogeneous group of non - langerhans cell histiocytoses , which are characterized by benign dermal proliferations of histiocytic cells in the absence of any known stimuli .
approximately 35% of cases of jxg occur at birth , with as many as 71% of cases occurring in first year .
usually , xanthogranuloma is termed as jxg though around 10% of cases manifest in adulthood . up to 81% of cutaneous jxg cases
extracutaneous jxg is rare ( 3.9% ) and most commonly involves eye . histopathological examination of jxg demonstrates a variety of findings . a time - dependant progression exists in development of characteristic histological features which correlates with age of lesions .
a mixed cellular infiltrate of neutrophils , lymphocytes , eosinophils and rarely mast cells may be noted .
anticipatory care , with patient reassurance , is appropriate because of self - limiting benign nature of disease .
ocular and systemic lesions may respond to steroids or radiotherapy . but diffuse and multiple cutaneous lesions also need some treatment .
a 28-year - old healthy male patient presented in our department with one - month history of diffuse numerous papulonodular eruptions at extremities , ears , face , and trunk .
cutaneous examination revealed yellow - brown , relatively well - demarcated papulonodular lesions with variable sizes ( 15 mm in diameter ) .
lesions were shiny , soft to elastic in consistency consistency present almost all over the body and majority being over upper and lower extremities , ears , and chin [ figure 1a  c ] .
the mucous membranes , palms and soles were unaffected and ophthalmologic examination was normal . no other systemic involvement was noted .
yellow - brown relatively well - demarcated shiny elastic papulonodular eruptions the following differential diagnosis was made : lepromatous leprosy , tuberous xanthoma and xanthogranuloma .
laboratory investigations , including routine hematological examination , liver and renal function test , were within normal range .
histopathological examination revealed dense granulomatous dermal infiltrates consisting of foam cells , giant cells ( mainly touton type ) , histiocytes , lymphocytes , and a few eosinophils and neutrophils mainly at upper dermis .
the epidermis was thinned out without any grenz zone and inflammatory cells extended toward lower dermis to subcutaneous tissue [ figure 2a  c .
granulomatous dermal infiltrates of foam cells , giant cells ( touton type ) , histiocytes , lymphocytes , neutrophils .
[ h & e stain ; original magnifications : 2b 10 ; 2a and c 40 ] the prognosis of disease was discussed with patient . as there was a diffuse involvement with disfigurement , we planed to give some treatment to improve disease process rapidly .
patient was reviewed after one month and noted about 50% reduction of size of lesion [ figure 3 ] .
he continued treatment for another one month and noticed that most of the lesions had flattened with yellowish and hyperpigmented macules [ figure 4 ] .
post - treatment photograph after one month of treatment post - treatment photograph after two month of treatment
serum lipid profiles are normal in patients with both juvenile and adult form of xanthogranuloma . the number of lesions in adult xanthogranuloma is lesser than in juvenile form . of 31 patients , 27 ( 87% ) with adult onset xanthogranuloma in japanese literature had a solitary lesion .
there seemed to be no definite sites of predilection for adult onset xanthogranuloma and lesions were usually asymptomatic .
spontaneous resolution does not occur in adult form , whereas juvenile form usually involutes spontaneously within a year .
earlier published report of nine cases of adult xanthogranuloma did not notice any spontaneous resolution .
extracutaneous involvements of eye , lung , testis and pericardium have been reported in patients with jxg .
in contrast , no concomitant extracutaneous lesions have been found in adult form , although solitary extracutaneous xanthogranuloma without cutaneous lesions have been reported .
these cells express phenotype of dermal dendrocytes , although a recent study has suggested that cell of its origin could be plasmacytoid monocytes .
the appearance of giant cell and foamy lipid - laden histiocyte occur late and they are almost certainly secondary events , possibly in response to cytokine production by the lesion histiocyte .
jxg has been noted in association with different diseases like neurofibromatosis , niemann - pick disease , urticaria pigmentosa , juvenile chronic myelogenous leukemia .
ocular and systemic lesions may respond to steroids or radiotherapy , and severe systemic jxg have required single and mutagenic chemotherapeutic regimens .
commonly , no treatment is necessary for cutaneous xanthogranuloma , but severe cutaneous involvement of adult form like our case may require some treatment to hasten disease improvement .
the growth of a number of tumor cell lines seems to be inhibited by retinoids , but response may be variable .
it affects transformed cell surfaces and leads to anchorage - independent growth , cell adhesiveness and density - dependant growth .
for these reasons , we started isotretinoin and noticed significant clinical improvement within two months .
as spontaneous resolution does not occur in adult xanthogranuloma , we think that this type of early resolution may be due to isotretinoin . but further large study is required to see the effectiveness of isotretinoin in xanthogranuloma .
xanthogranuloma is a benign , asymptomatic , and self - healing disorder of non - langerhans cell histiocytosis , affecting mostly infants , children , and rarely adults . 
 diagnosis is easy in typical cases but become more complex in unusual forms . 
 we report a case of a 28-year - old male patient who presented with multiple diffuse brown - to - yellowish papulonodular eruptions over extremities , ears , face , trunk , and extensors of joints with almost bilaterally symmetrical distribution for a period of one month . 
 histopathological examination of the skin biopsy specimen revealed features of xanthogranuloma . 
 the patient was put on isotretinoin 20 mg once daily . 
 most of the lesions subsided or flattened within two months of isotretinoin therapy . 
 this case is interesting because of the severity and atypical nature of the disease and also , the patient responded with isotretinoin therapy . but further study is required to observe the effectiveness of isotretinoin in xanthogranuloma .