Patterns of Priapism in Sickle Cell Disease.
Authors: Redding-Lallinger Rupa , Muldrow Warrick 
Published: April 2020

Abstract
In this study priapism is defined as a prolonged erection (&gt; 45 minutes in the absence of sexual stimulation) or any painful erection. Boys and young men with SCD were eligible to participate in completing daily diary pages and overnight hormonal monitoring; the data presented are from 1486 diary days collected from 6 young men with mean age of 20.7 years (range 17 to 23). One subject is SCD-SC and the others SCD-SS. Three had had priapism in the 6 months preceding the study and three had not.
Erections and Priapism by Subject Subject Diary&#x2028; Days Days w/any Erection (Erection Days) Erection Days as % of Diary Days Total Days w/Priapism (Priapism Days) Priapism Days as % of Erection Days 1 244 69 28 16 23 2 290 216 74 5 2 3 302 106 35 54 51 4 278 125 45 8 6 5 318 21 7 10 48 6 54 29 54 7 24 Total 1486 566 38 100 18 Mean 248 94 41 17 26
Characterization of Priapism: Priapism occurred on an average of 6.7% of diary days. Eighty-four percent of these episodes were painful but not prolonged, ten percent were prolonged but not painful, and 4% were both. Of the painful erections, 42% lasted &lt;15 minutes, 45% were &gt;15 to 45 min, and 12% were &gt;45 min to 3 hrs. The mean pain score was 4.3 out of 10. Painful events occurred most frequently between 6 am – 12 noon (37%); midnight (MN) to 6 am was the next most frequent time (29%). Erections occurred on 36% of days following a day with priapism; 75% of these erections were also painful or prolonged.
Priapism and Normal Erectile Function: Erections occurred on a mean of 38% of all diary days. The proportion of erection days which were priapism days were .02, .06, .23, .24, .48 and .51 for the 6 subjects. Normal erections occurred most frequently between 6am – 12 noon (45%); 6pm – 12 MN was the next most frequent time (24%). Sexual activity (sex), defined as viewing stimulating media, masturbation, sexual intercourse or contact was reported on 22% of the total diary days. On 72% of days where sex was reported, erections were reported, vs 28% of days with no sex. Of erection days, painful erections were reported on 12% where sex occurred and on 20% of days where no sex occurred. Erection days were 50% of days following days with sex, vs 33% of days following days without sex. On erection days following sex days participants reported painful erections on 14% of the days versus 17% of the days following days with no sex.
Conclusions: The data suggest some differences with the usual conception of priapism. Most of the episodes which the individuals reported as painful were short, the majority between 15 and 45 minutes, and a sizeable minority were &lt; 15 minutes. The proportion of all erections that were priapic varied greatly within the group, but for 4 of the 6, 25–50% of days on which there was any erection there was priapism. The relationship between sexual activity and priapism in these data suggests fewer painful erections on days where there are both sex and erections, than on days when there are erections but no sexual activity. This is also true on the day following a day with sex—if any erection occurs on these days, fewer are painful than on erection days that occur after a day with no sex. Confirmation of the trends awaits the analysis of more subjects.