What Does An ESR Of 40 Indicate In A Child With Chronic Nosebleeds And Hives?

Good evening doctors. My grandson , 9 years old, has an ESR of 40 mm/ hr. What does this mean? He has chronic nosebleeding and for about 2 months ago, until now, he has hives all over his body even with care of his food intake. It subsides only when administered with antihistamines .Thank you.