Child losing weight now

My daughter just had her 18-month appointment. She was 22 pounds at her 15 month appt. and in the 50 percentile. She dropped dramatically at this last appt. She is now 21 pounds 9 ounces. She didn't appear to grow in height either. She was not walking very well at her 15 month appt. and now she is very active. Could this weight loss be due to her active level? She eats extremely well. In fact, she eats better than her almost 4 year old sister. She also drinks a ton of whole milk. And from all appearances she is very happy and healthy. She has a constant runny nose (that is clear at this time) but that doesn't seem to bother her and it seems most children have a runny nose at this age. Her pediatrician wants to see her in 3 months for another weight check and I was fine with that until some medical friends starting suggesting a cystic fibrosis test. Please tell me what you think?

[Renee Radenberg]

CF children do stop gaining weight. It is one of the first signs of the disease but I would not jump to that conclusion at this point. She only lost 3oz from the last check-up, however, she has increased her activity level. It is great she has a good appetite. I suggest you give her a daily children chewable multi-vitamin, give her nutrient dense drinks, such as Pedisure or milkshakes instead of milk, and more food protein sources (meats). Maybe this will help her to gain weight. If she still has not gained weight after 3 months then talk to your MD what they think it might be.