If the onset of mono had preceded the strong abdominal pains, it is possible that it caused hepatitis, leading to abdominal pains among the classic / hallmark mono symptoms.
Often mono diagnosis gets missed at the beginning, however it does cause inflammation of the liver in about 10% of the patients.
5th disease may also cause liver inflammation.
The liver is involved in a gazillion important functions
like blood cleansing, energy management, hormone regulation, production of numerous essential substances to facilitate various bodily functions and so on.
Some of these functions depend on the integrity of the liver and when the liver is inflamed, detoxification, metabolism,
digestion, immunity, etc. get compromised.
Has the possibility of a mono reactivation been explored?
The risk of infection and re-infection is greater when the liver is affected, naturally. If this is the case indeed, it is like a double edged sword.
How about her biliburin levels? Were they elevated?
There's a Diagnostic Algorithm that maps out the dx process in some logical manner.
If interested do a search under :
Pediatr Gastroenterol Hepatol Nutr. 2013 Dec; 16(4): 225–232. Then go to table 1 and open it by clicking on it.
Best wishes,
Niko