adult onset still 's disease ( aosd ) is a systemic inflammatory disorder of unknown etiology characterized by spiking fever , evanescent salmon - pink skin rash , polyarthralgia or polyarthritis , involvement of various organs and predominantly neutrophilic leucocytosis . the diagnosis is one of clinical suspicion , requiring the exclusion of infection , malignancy , and systemic disease . the typical still 's rash is transient , asymptomatic macular or maculopapular and has a characteristic salmon - pink colour . it is regarded as a major diagnostic criterion with high sensitivity and specificity . adult - onset still 's disease ( aosd ) is a systemic inflammatory disorder of unknown etiology characterized by spiking fever , evanescent skin rash , arthralgia or arthritis , involvement of various organs , and predominantly neutrophilic leucocytosis . we report a case which illustrates the typical features of aosd that were treated with steroids and azathioprine . a 23-year - old male was admitted for acute viral myopericarditis with heart failure in which he presented with chest pain associated with dyspnoea , persistent spiking fever with temperature more than 39c , sore throat , productive cough , and arthralgia . in addition , he developed transient non - pruritic rashes over the neck , axillae , and limbs . he had cervical lymphadenopathy , hepatosplenomegaly , and non - scaly orange red plaques and papules over the neck , axillae , and limbs [ figures 1 and 2 ] . urticated and erythematous plaques and papules on the dorsum of right hand and fingers urticated plaques over the right antecubital fossa laboratory investigations revealed raised cardiac enzymes , positive troponin i , ecg changes consistent with pericarditis , marked leucocytosis with neutrophil predominance , hyperferritinemia , and elevated erythrocyte sedimentation rate ( esr ) and c - reactive protein ( crp ) . the rheumatoid factor ( rf ) , anti - nuclear antibody ( ana ) , and anti - dsdna were negative . histopathological examination of the skin biopsy revealed features of a neutrophilic dermatosis [ figure 3 ] . he was diagnosed with aosd as he had four major and three minor criteria for this entity according to the yamaguchi 's criteria [ table 1 ] . histology shows superficial and deep perivascular infiltrates of lymphocytes and neutrophils with neutrophils in between collagen bundles yamaguchi 's criteria for diagnosis of adult - onset still 's disease he was treated with steroids , diclofenac and azathioprine , which controlled the rash and improved the arthralgia . aosd is a systemic inflammatory disorder of unknown etiology characterized by spiking fever , evanescent salmon - pink skin rash , polyarthralgia or polyarthritis , involvement of various organs and predominantly neutrophilic leucocytosis . the diagnosis is one of clinical suspicion , requiring the exclusion of infection , malignancy , and systemic disease . a number of authors have proposed a diagnostic criteria for aosd with the most sensitive being the one proposed by yamaguchi et al . patients who have aosd commonly present with fever which is classically described as quotidian , with temperature spiking once a day to 39c or higher , usually in the evening or night as in our patient . the typical still 's rash is transient , asymptomatic macular , or maculopapular and has a characteristic salmon - pink color . various atypical skin lesions such as persistent pruritic plaques have been reported in sporadic cases with active aosd . it is characterized by necrotic keratinocytes in the upper half of epidermis with a neutrophilic infiltrate in the papillary dermis histologically . our patient presented with myopericarditis with congestive cardiac failure and pleural effusion which is a rare manifestation that has been reported in previous literature . myocarditis is a known complication in aosd and may result in cardiac failure or arrhythmia . it is therefore imperative to screen and investigate patients for cardiac involvement , particularly those presenting with chest pain , tachycardia , or mild st elevations on ecg . the most striking abnormality is a marked leucocytosis with neutrophilic predominance as seen in our patient . marked hyperferritinemia associated with diminished concentration of glycosylated ferritin is a characteristic feature of aosd . there is often a relatively sparse perivascular mixed inflammatory infiltrate containing some neutrophils as seen in our patient . the management of aosd is first directed at the acute systemic features of the disease . in chronic disease , arthritis is the major concern . treatment consists of non - steroidal anti - inflammatory agents ( nsaids ) , corticosteroids , disease modifying anti - rheumatic drugs ( dmard ) , immunosuppressive agents , and intravenous gamma globulin ( ivig ) . the recent successful application of biologic agents , often in combination with traditional immunosuppressive agents , has been very promising . immunosuppressive agents including methotrexate , azathioprine , and cyclosporine a have been used as second - line drugs in the treatment of aosd . in our case , aosd , although uncommon , has characteristic constellation of clinical and laboratory features and should be considered in the differential diagnosis of pyrexia of unknown origin associated with a rash and arthralgia . the diagnosis is one of clinical suspicion and it is essential that infections , malignancy , and other rheumatic diseases are excluded . various atypical skin lesions such as persistent pruritic plaques and prurigo pigmentosa - like lesions have been reported in sporadic cases with active aosd . there were frequent reports of aosd patients who presented with pruritic persistent papules and plaques clinically . a recent case series demonstrated that it is characterized by necrotic keratinocytes in the upper half of epidermis with a neutrophilic infiltrate in the papillary dermis histologically . this type of rash may represent a specific manifestation of this syndrome and awareness of the distinctive pathologic features of persistent plaques and papules may facilitate an earlier diagnosis of aosd.myocarditis is a known complication in aosd and may result in cardiac failure or arrhythmia . therefore it is imperative to monitor patients closely with routine ecgs and echocardiographies in aosd patients presenting even with vague signs of myocarditis such as chest pain , tachycardia or mild st - elevations on ecg . various atypical skin lesions such as persistent pruritic plaques and prurigo pigmentosa - like lesions have been reported in sporadic cases with active aosd . there were frequent reports of aosd patients who presented with pruritic persistent papules and plaques clinically . a recent case series demonstrated that it is characterized by necrotic keratinocytes in the upper half of epidermis with a neutrophilic infiltrate in the papillary dermis histologically . this type of rash may represent a specific manifestation of this syndrome and awareness of the distinctive pathologic features of persistent plaques and papules may facilitate an earlier diagnosis of aosd . myocarditis is a known complication in aosd and may result in cardiac failure or arrhythmia . therefore it is imperative to monitor patients closely with routine ecgs and echocardiographies in aosd patients presenting even with vague signs of myocarditis such as chest pain , tachycardia or mild st - elevations on ecg .
adult onset still 's disease ( aosd ) is a systemic inflammatory disorder of unknown etiology characterized by spiking fever , evanescent skin rash , arthralgia or arthritis , involvement of various organs , and predominantly neutrophilic leucocytosis . 
 aosd , although uncommon , has a characteristic constellation of clinical and laboratory features and should be considered in the differential diagnosis of pyrexia of unknown origin associated with a rash and arthralgia . 
 the diagnosis is one of clinical suspicion and it is essential that infections , malignancy , and other rheumatic diseases are excluded . 
 we report a case which illustrates the typical features of aosd that were treated with steroids and azathioprine .