Yes. That is a high level so moving out to 6 weeks is what most docs would do.
Keep in mind that Studies of infliximab show that risks do not increase with dose escalation so it is not that your son was at an unsafe level as much as at a certain point you are just wasting medicine, money and time.
young children, the clearance of infliximab has been estimated to be more rapid and to achieve target levels of the drug, higher doses around 10 mg/kg and shortening of the interval to 4–5 weeks may be needed (41). A recent study summarized data from 215 patients with PIBD treated with infliximab and with trough level measurements during induction and maintenance. Regarding patients younger than 10 years of age, two thirds of the patients had trough levels below the target level at the start of the maintenance therapy. After one year of therapy, the dose requirements and risk to develop drug antibodies were higher in the group of young patients compared to the older patient group (41). The therapeutic outcome in the young patients, however, was not different from the older patients (24, 41). However, it is not just weight or age of the patients that have an impact on the trough levels and the outcome of the therapy. The level of inflammation as reflected in the levels of albumin and inflammatory markers is a key player in drug pharmacokinetics (42). Therefore, in patients with high inflammatory load, higher dosing of infliximab is needed to reach target levels (3, 5). Disappointingly, a recent report stated that although trough levels during induction therapy with infliximab increased and antibody formation decreased, the proportion of pediatric patients maintaining their therapeutic response during the first year did not increase (20). It is not clear why some patients with trough levels considered as adequate, lose their therapeutic response. As this may occur after several months of maintenance therapy, it has been suggested that in these late non-responders the inflammatory pathway is altered and becomes resistant to TNFα blockade (43, 44). Indeed, the initial response to infliximab therapy during induction is predictive for the long-term outcome of the therapy both in children and in adults with IBD. Patients with low levels of fecal calprotectin at the end of induction are more likely to have a favorable long-term outcome compared to patients with elevated levels of fecal calprotectin reflecting ongoing inflammation after induction (7, 45).
Results: Twenty-four of thirty-four subjects (71%) achieved clinical remission at week 8. The median infliximab concentrations were 33.0 μg/mL (interquartile range: 26.5–52.1 μg/mL) pre-dose #2 and 22.5 μg/mL (interquartile range:15.9–32.3 μg/mL) pre-dose #3. Trough pre-dose #2 infliximab concentration yielded area under receiver operator characteristic curve 0.7, 95% CI: 0.5–0.9 in predicting week 8 clinical remission; a cut-off of 33.0 μg/mL yielded 62.5% sensitivity, 66.7% specificity. Trough pre-dose #3 infliximab concentrations were lower for subjects <10 years compared to ≥ 10 years [median 15.9 μg/mL, interquartile range (IQR) 8.5–21.8 μg/mL vs. 27.7 μg/mL, IQR 17.2–46.7 μg/mL, p = 0.01] and correlated with baseline weight (Spearman's rank correlation coefficient 0.45, p = 0.01). The median half-life following first IFX dose was 6.04 days (IQR 5.3–7.9 days).
Conclusions: Infliximab concentrations ≥33 μg/mL prior to the second dose were associated with week 8 clinical remission. As young age and low body weight impact infliximab concentration, prospective studies with proactive adjustment in pediatric patients with ulcerative colitis should be carried out. Clinicians caring for children with UC should diligently adjust and monitor infliximab to optimize response.
That was my guess - age plays a factor. M's pediatric rheumatologist was willing to go to 20 mg/kg for Remicade - she spent quite a while on that dose with no adverse effects. I think her adult rheumatologist and adult GI would be horrified at that dose! Actually, the first thing her adult rheumatologist said when M said she'd been on 20 mg per kg was that she had been on the "kiddie dose" - M was quite offended because she was in her late teens when she was on that dose (and of course when they're 18-19, they think they're grown up ).I think age plays a big factor in levels
Adults (18+) should be fine at 10
But little kids tend to burn through meds at a faster rate
No...he is not taking anything other than infusion for every 8 weeks.Hi there, you mentioned that the increase was just last Monday. He may need a little more time for the increase to make a difference. When my son was increased from 5 mg to 10 mg, it did make a difference but it did take a few months for symptoms to completely resolve. Is your son on any other medication?
As for his other symptoms, like others have said, it may take a few infusions at the higher dose for those to go away. Sometimes using proctofoam or hydrocortisone suppositories in the interim can really help.He is having symptoms of heaviness and uncomfortable feeling in the anal area after the bowel movement. To address these issues they increased the dosage from 5 to 10 mg. I have not seen any improvement in these issues
He is 12 years old. He is very good chess player. He got diagnosed last year August and was on strict diet since then thinking that he can get away without going for infusions. But he started taking Remicade from May 8th after his symptoms getting worse. Last Monday infusion was his 4th one. We got an appointment with urologist on September 1st.@sairm How old is your son? Jo-mom is right the increase could take awhile to resolve all symptoms. As for the new symptoms, it could just be a run of the mill UTI, did you make that appointment with his pediatrician? You might get faster answers as far as possible UTI at the pediatrician.
8 week spacing at diagnosis is most likely much too far of a spread. It took us a year and a half to get to 6 weeks.
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Thank you all for valuble information. Got response from my sons GI to check drug level before next infusion(Oct 20th) to see whether it requires to be adjusted. They did MRE in the anal region and it looks almost good except mild inflammation. Doctor was saying he needs to do scope to see what exactly is causing his symptoms. Not sure whether gor for it or wait few more weeks to see whether last week's infusion will do some help. Regarding his bladder issues, went to pediatric urologist yesterday. He said it might be because of overreacting bladder and prescribed some medication to relax it. So fat not seeing much help for medication. Need to call in office to see what is next step. He is having tough time from all these symptoms.
Apologies for not reading the entire thread.
The normal range for lymphocytes varies with age. 4880 seems completely normal.
The upper limit of normal is higher in children, especially younger children. I wonder where the labs reference range is from snd if it’s age
Med News Today says “The normal lymphocyte range in adults is between 1,000 and 4,800 lymphocytes in 1 microliter (µL) of blood. In children, the normal range is between 3,000 and 9,500 lymphocytes in 1 µL of blood.”
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I have a question. Had an infusion last Monday, all his bloodwork including iron levels were in range. His remicade trough level came back at 5.4, when it was tested in Dec'23 it was 13.5, Aug'23 it was 9.8, Apr'23 14.7. Currently we are spaced at 6 weeks. Does anyone have experience with a drop off like that? And could the fact that has had strep impact his level? His Doc suggested possibly moving his next infusion up to 4 weeks, or re testing the level at 6 weeks, and seeing if it was a fluke.