text: Yo, check it out, listen up, I got a story to tell,
  'Bout PBC and MS, diseases from hell.
  Autoimmune conditions, with causes complex,
  Genetic predisposition and triggers, what's next?
  
  PBC and MS, they walk hand in hand,
  A connection observed, in sporadic lands.
  Fingolimod, a drug, it's got some power,
  Fights MS, makes symptoms cower.
  
  But here's a twist, pay attention, don't miss,
  A case we describe, it's a story like this.
  A 34-year-old dude, with relapsing MS,
  Taking fingolimod, hoping for success.
  
  But suddenly, boom, a syndrome unfolds,
  PBC-like symptoms, the story unfolds.
  Did EBV reactivate, or was it pure fate?
  Concurrently or consequently, it's hard to state.
  
  Infections and medications, a tangled web,
  Unmasking conditions, like a punch to the head.
  This case shows us, the risks we must heed,
  When treating MS, take caution, indeed.