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quantitative computed tomography scans in cohort of 74 patients (aged 5–21) initi-
ating anti-TNF therapy [ 55 ]. Trabecular BMD Z-scores were lower in IBD patients
compared to healthy reference participants at baseline and negatively correlated
with PCDAI. Trabecular BMD Z-scores and cortical structure improved over the
12-month observation interval; younger age was associated with greater increase in
trabecular BMD Z-scores, but deficits in trabecular BMD Z-scores remained.
Vitamin D plays also an important role in bone homeostasis, and suboptimal, insuf-
ficient, and deficient vitamin D has been noted in pediatric IBD [ 56 ]. A recent study
of 87 patients with CD, 80 of whom were aged 5–20, assessed short-term changes
in vitamin D and mineral metabolism after anti-TNF induction therapy [ 57 ].
Although no changes were seen in 25-hydroxyvitamin D (21-OH D), PTH and 1, 25
dihydroxyvitamin D (1, 25-OH D) increased significantly after induction therapy,
indicating improved renal conversion of 25-OH D. Although long-term data is lim-
ited, these studies suggest a role of anti-TNF therapy in improving short-term bone
health in pediatric patients, which, in addition to improvement in linear growth,
nutritional support, correction of vitamin D deficiency, and weight-bearing activi-
ties, may positively impact future skeletal health.
Vaccination Strategies in Pediatric IBD on Anti-TNF Therapy
Vaccination for prevention of disease is of utmost importance in the pediatric IBD
population given the immunosuppression which results from most therapies, includ-
ing anti-TNF agents. It is recommended that all IBD patients receiving biologic
therapy be administered with routine inactivated vaccines according to the recom-
mended schedule detailed by the American Academy of Pediatrics, the Advisory
Committee on Immunization Practices, and Centers for Disease Control and
Prevention. This includes vaccination for hepatitis A, hepatitis B, diphtheria, teta-
nus, pertussis, Haemophilus influenzae B, pneumococcus (PCV) (13 valent and 23
valent), polio (intramuscular vaccine), and influenza in early childhood and human
papilloma virus and meningococcal disease during school age and adolescents.
Administration of live virus vaccines, which include rotavirus; intranasal flu vac-
cine; measles, mumps, and rubella (MMR); varicella; oral polio; oral typhoid; her-
pes zoster; and yellow fever, is contraindicated in pediatric IBD patients receiving
anti-TNF therapy. If clinical presentation allows, these vaccines should be adminis-
tered several weeks (≥4 weeks for MMR vaccination) prior to initiating immuno-
suppression or several months after stopping these therapies. Live virus vaccinations
such as MMR, varicella, zoster, and rotavirus are not contraindicated in household
members of children with IBD on anti-TNF therapy, but vaccine recipients should
monitor symptoms, and if vaccine-related symptoms such as rash or diarrhea
develop, the recipient should avoid contact with the patient with IBD if he/she has
not been appropriately vaccinated [ 58 ].
Ideally, inactivated vaccines should be administered at least 2 weeks prior to
initiation of immunosuppressive therapy to improve efficacy; however, several
S. Patel and J. Strople