this 41-year - old housewife , educated up to sixth standard , hailing from middle socioeconomic status , with nil contributory family history , and suffering from hypertension and myopia in left eye ( + 0.75 ) and hypermetropia in right eye ( 0.75 ) , reported to outpatient clinic with history of 10-years duration characterized by unpleasant , frequent , and distressing doubts related to dirt and contamination .
these resulted in performance of long , nonfunctional repetitive activities like cleaning and saying same words again and again .
it was also reported both by husband and the patient herself that these symptoms have a seasonal pattern appearing in october and complete resolution in april - may .
this seasonal pattern was so well - recognized that no treatment was taken for initial 3 - 4 years as they considered it an effect of change of season and that symptoms would disappear once the winter is over .
no associated stress or precipitating factor was identified that might lead to reoccurrence of these symptoms every year in winter . gradually over the years she noted that the severity of her illness increased and was causing socio - occupational dysfunctions .
therefore , this year she reported for psychiatric treatment at the beginning of october . on mental state examinations she had obsessions of contamination , compulsions for washing , and assurance seeking .
the severity of symptoms was assessed by administrating yale  brown obsessive compulsive scale ( y - bocs ) .
the total y  bocs score was 30 ( obsessions score 17 and compulsions score 13 ) , other routine investigations were within normal limit .
other than ocd in subsequent follow - ups , patient was also diagnosed as having cervical spondylitis .
she was on fluoxetine 20 mg once daily for 1month , but did not show much improvement .
therefore , keeping in view the seasonal variation in the pattern of oc symptoms , she was also considered for phototherapy .
she was also taken up for exposure and response prevention ( erp ) therapy twice a week for 1hour , where therapist assisted the patient in exposure .
her y - bocs score came down to 8 ( 5 for obsession and 3 for compulsion ) and she was discharged on fluoxetine 20 mg once daily maintenance treatment .
epidemiological studies have found the prevalence rates of sad to be generally higher in northern locations like north america and europe , and generally lower in warmer , tropical countries .
however , the influence of latitude in prevalence of ocd is yet to be established by cross - sectional surveys from different countries . studies also suggest that seasonal ocd is rare in prevalence and difficult to diagnose .
one reason might be the requirement of long history with respect to seasonality is required for establishing diagnosis . in a large - scale study of children in united states aged 9 - 17 years , significant seasonal variations were found in overanxious disorder , ocd , separation anxiety disorder , social phobia , and major depressive disorder , with worsening of symptoms in august - october .
similarly , a retrospective study of 34 patients with ocd found that 53% patients with ocd reported a marked seasonal variation in their symptoms .
while the reasons for the seasonal variation in ocd symptoms is not known , alterations in monoaminergic neurotransmission in the brain are believed to be the reason for seasonal variations in mood disorders . in a study of 101 healthy men , it was found that the turnover of serotonin by the brain was lowest in winter .
moreover , the rate of production of serotonin by the brain was directly related to the duration of bright sunlight , and increase rapidly with greater duration of sunlight .
these findings are supportive of the notion that changes in release of serotonin by the brain may underlie seasonal variations in ocd .
the alteration of brain serotoninergic systems in ocd supports the use of light therapy for the treatment of ocd .
in fact , just like in the present case , a reduction in oc symptoms by bright light therapy has been reported earlier in a patient having seasonal variation in ocd .
can these variations in symptoms be solely attributed to climate ( light ) changes or there are factors that still remain unexplored .
it is also questionable whether the response is because of anti - obsessional drugs or it was just a placebo effect of the drug therapy .
a careful prospective study of seasonal pattern of ocd will help in understanding symptoms , course , and suitable treatment options in such cases .
different clinical course and treatment response indicates different and/or overlapping neurobiological basis for the seasonal ocd . is seasonal variation of ocd different from ocd unrelated to seasons ?
our case had contamination obsession and washing compulsion , but whether seasonal ocd manifest in other types like aggression , sexual , hoarding or symmetry , and whether it may be classified as  reactive or 
further it can be speculated that , like sad , seasonal ocd may be of some diagnostic value or can be taken as part of spectrum or a course specifier in nosology .
 a case of obsessive - compulsive disorder ( ocd ) with seasonal variation in symptoms of 10-years duration is reported because of its rarity . 
 the phenomenology of the observed disorder was obsessions related to dirt and contamination resulting in washing compulsions with onset in october and complete resolution in april - may every year . 
 the patient responded to phototherapy along with exposure and response prevention therapy and pharmacotherapy . 
CASE REPORT
DISCUSSION