▁used ▁to ▁refer ▁to ▁primary ▁my el of ib ros is . ▁ ▁Sign s ▁and ▁sympt oms ▁The ▁primary ▁feature ▁of ▁primary ▁my el of ib ros is ▁is ▁b one ▁mar row ▁fib ros is , ▁but ▁it ▁is ▁often ▁accompanied ▁by : ▁ ▁Ab dom inal ▁full ness ▁related ▁to ▁an ▁en larg ed ▁s ple en ▁( spl en om eg aly ). ▁B one ▁pain ▁Bru ising ▁and ▁easy ▁ble eding ▁due ▁to ▁in ade qu ate ▁numbers ▁of ▁plate lets ▁C ach ex ia ▁( loss ▁of ▁app et ite , ▁weight ▁loss , ▁and ▁fat igue ) ▁En larg ement ▁of ▁both ▁the ▁li ver ▁and ▁s ple en ▁F at igue ▁G out ▁and ▁high ▁u ric ▁acid ▁levels ▁In cre ased ▁sus cept ibility ▁to ▁in fection , ▁such ▁as ▁p neum onia ▁ ▁P all or ▁and ▁short ness ▁of ▁breath ▁due ▁to ▁an emia ▁In ▁r ar er ▁cases , ▁a ▁raised ▁red ▁blood ▁cell ▁volume ▁▁ ▁C ut aneous ▁my el of ib ros is ▁is ▁a ▁rare ▁skin ▁condition ▁character ized ▁by ▁der mal ▁and ▁sub cut aneous ▁nod ules . ▁ ▁C aus es ▁There ▁is ▁an ▁association ▁between ▁mut ations ▁to ▁the ▁J AK 2 , ▁C AL R , ▁or ▁M PL ▁gene ▁and ▁my el of ib ros is . ▁Appro xim ately ▁ 9 0 % ▁of ▁those ▁with ▁my el of ib ros is ▁have ▁one ▁of ▁these ▁mut ations ▁and ▁ 1 0