What are the opening hours?

Monday 9am - 4pm Tuesday 9am - 4pm Wednesday 9am - 4pm Thursday 9am - 4pm Friday 9am - 4pm

Peirson Center for Children, 9820 E Burnside Street, Portland, OR (2026)

08/29/2026

Low Neutrophil Count in Down Syndrome: Common Does Not Mean “Normal”

Children and adults with Down syndrome appear to have an increased tendency toward low neutrophil counts. However, a low neutrophil count should not automatically be dismissed as simply being “part of Down syndrome.” Neutropenia deserves further evaluation in every patient.

What are neutrophils?

Neutrophils are a type of white blood cell and an important part of the innate immune system, the body's rapid first-line defense against infection.

They are among the first immune cells recruited when bacteria or fungi invade the body. Neutrophils can engulf and destroy microorganisms, release antimicrobial substances, and help coordinate the inflammatory response that recruits other immune cells to an infection.

When evaluating neutrophils, the most useful measurement is the absolute neutrophil count (ANC) rather than simply the percentage of neutrophils reported on a CBC.

It is also important to use an age-appropriate reference range. Normal neutrophil counts change considerably throughout infancy and childhood.

Mayo Clinic Laboratories provides the following age- and gender-specific reference ranges:

MALES
• 0-14 days: 1.60-6.06 × 10⁹/L
• 15 days-4 weeks: 1.18–5.45 × 10⁹/L
• 5-7 weeks: 0.83-4.23 × 10⁹/L
• 8 weeks-5 months: 0.97-5.45 × 10⁹/L
• 6-23 months: 1.19-7.21 × 10⁹/L
• 24-35 months: 1.54-7.92 × 10⁹/L
• 3-5 years: 1.60-7.80 × 10⁹/L
• 6-16 years: 1.40-6.10 × 10⁹/L
• 17 years: 1.80-7.20 × 10⁹/L
• Adults: 1.56-6.45 × 10⁹/L

FEMALES
• 0-14 days: 1.73-6.75 × 10⁹/L
• 15 days-4 weeks: 1.23-4.80 × 10⁹/L
• 5-7 weeks: 1.00-4.68 × 10⁹/L
• 8 weeks–5 months: 1.04-7.20 × 10⁹/L
• 6-23 months: 1.27-7.18 × 10⁹/L
• 24-35 months: 1.60-8.29 × 10⁹/L
• 3-5 years: 1.60-7.80 × 10⁹/L
• 6-14 years: 1.5-6.50 × 10⁹/L
• 15-17 years: 2.00-7.40 × 10⁹/L
• Adults: 1.56-6.45 × 10⁹/L

https://www.mayocliniclabs.com/test-catalog/overview/9109/complete-blood-cell-count-cbc-with-differential-blood -and-interpretive

What can cause a low neutrophil count?

There are many possible causes of neutropenia. It may be temporary, particularly during or following a viral infection. Persistent neutropenia has a broader differential diagnosis that includes infections, medications, autoimmune conditions, immune disorders, congenital conditions, bone marrow disorders, and nutritional deficiencies.

Nutritional causes are particularly important not to overlook. In our clinical experience, nutritional insufficiencies are among the most common contributors we identify in our patients with Down syndrome and low neutrophil counts. Fortunately, they are also among the most easily addressed.

A review published in Seminars in Hematology states:
“Nutritional deficiencies of vitamin B12, folic acid or copper, or severe protein-calorie malnutrition can cause neutropenia.”
https://pmc.ncbi.nlm.nih.gov/articles/PMC3748385/

The authors note that nutritional deficiencies typically cause abnormalities in more than one blood-cell line rather than isolated neutropenia. Nevertheless, vitamin B12, folate, copper, and overall nutritional status should be considered when investigating chronic neutropenia.

This may be particularly relevant in Down syndrome because feeding difficulties, restricted diets, gastrointestinal disorders, and nutrient malabsorption can contribute to nutritional deficiencies.

Other important causes of low neutrophils include infection and bone marrow disorders. Neutrophil counts can temporarily fall during or after a viral infection because infection can suppress neutrophil production in the bone marrow and can also increase their use, destruction, or movement out of the circulating blood.

More serious bone marrow disorders, including leukemia, can also cause neutropenia when abnormal cells interfere with normal blood-cell production. Warning signs that warrant particular attention include persistent or recurrent fever or infections, unusual bruising or bleeding, petechiae, pallor, significant fatigue or weakness, bone or joint pain, unexplained weight loss, enlarged lymph nodes, or enlargement of the liver or spleen. Leukemia may also cause abnormalities in other blood-cell lines, such as a low red blood cell or platelet count.

A temporary decrease in circulating neutrophils can also occur following vaccination, most often within the first two weeks. This may reflect redistribution of neutrophils as part of the immune response and other transient immune effects. Although post-vaccination neutropenia often resolves on its own, a low neutrophil count still warrants follow-up to confirm that it returns to an appropriate range.
https://pmc.ncbi.nlm.nih.gov/articles/PMC4974007/

Evaluation should consider:

• The appropriate age- and gender-specific reference range
• Whether the ANC has been low on previous CBCs
• Whether the neutropenia is transient or persistent
• Whether other blood-cell lines are also abnormal
• Recent infections
• Medications
• Vitamin B12, folate, copper, and overall nutritional status
• Immune and autoimmune causes

In our practice, we follow up a low neutrophil count by checking serum vitamin B12, folate, copper, and zinc to evaluate for potentially correctable nutritional contributors. Depending on the degree and persistence of the neutropenia, the clinical history, and other CBC findings, additional evaluation and/or referral to hematology may also be appropriate.

A finding can occur more often in Down syndrome and still deserve investigation. A low neutrophil count should always prompt us to ask why, look for potentially correctable causes, and take action when appropriate.

References:

Newburger PE, Dale DC. Evaluation and Management of Patients with Isolated Neutropenia. Semin Hematol. 2013;50(3):198–206.

Mayo Clinic Laboratories. Complete Blood Cell Count (CBC) with Differential, Blood: Pediatric and Adult Reference Values.

Muturi-Kioi V, Lewis D, Launay O, et al. Neutropenia as an Adverse Event following Vaccination: Results from Randomized Clinical Trials in Healthy Adults and Systematic Review. PLoS One. 2016;11(8):e0157385.

08/25/2026

How much choline does a woman really need during pregnancy? 🧠

The current recommended intake of choline during pregnancy is 450 mg/day. But some fascinating research suggests that this may not be enough to optimally support fetal brain development.

In a randomized, controlled feeding study, researchers at Cornell University compared pregnant women consuming approximately the recommended amount of choline (480 mg/day) with women consuming about twice that amount (930 mg/day) during the third trimester.

The babies whose mothers consumed 930 mg/day had significantly faster information-processing speeds during their first year of life compared with babies whose mothers consumed 480 mg/day. Importantly, no adverse effects were reported at either intake level.

But here's the part we find especially interesting:

Researchers followed these children until 7 years of age.

Children whose mothers had consumed 930 mg/day during pregnancy performed significantly better on a test of sustained attention than children whose mothers consumed 480 mg/day. The researchers concluded that the higher prenatal choline intake produced lasting improvements in sustained attention.

Choline is critical for the developing brain. It's needed to make acetylcholine, an important neurotransmitter involved in attention and learning, as well as phosphatidylcholine and sphingomyelin, important components of cell membranes and myelin. Choline also contributes to methylation and regulation of gene expression.

And yet, most pregnant women aren't even reaching the current recommendation. The researchers note that average intake during pregnancy in North America is only around 350 mg/day, and many prenatal vitamins contain little or no choline.

These are just two examples from a growing body of research supporting the importance of adequate choline intake during pregnancy for fetal brain development and long-term neurodevelopmental outcomes. They raise an important question: Is the current choline recommendation during pregnancy high enough to optimally support a baby's developing brain?

Supporting optimal brain development begins before birth, and choline is emerging as a particularly important piece of that picture.🧠💚

Bahnfleth CL, et al. Prenatal choline supplementation improves child sustained attention: A 7-year follow-up of a randomized controlled feeding trial. FASEB J. 2022.
https://pmc.ncbi.nlm.nih.gov/articles/PMC9303951/

Caudill MA, et al. Maternal choline supplementation during the third trimester of pregnancy improves infant information processing speed: a randomized, double-blind, controlled feeding study. FASEB J. 2018.
https://pmc.ncbi.nlm.nih.gov/articles/PMC6988845/

08/19/2026

The MAPS Parent Conference is back this fall in Philadelphia!

Created specifically for parents navigating complex chronic and developmental conditions, this is a space to learn directly from MAPS clinicians, ask questions, connect with other families, and leave with deeper understanding and practical support.

Join us in person for expert education, parent-focused conversations, and the connection that made our first Parent Conference so special.

Dr. Peirson will also be speaking at the MAPS conference in the physician track that weekend!

📅 September 13, 2026
📍 Philadelphia, PA
💻 Virtual option available

Learn more + register:

➡️ https://www.medmaps.org/events/fall2026-parent-conference/

08/18/2026

Down syndrome results from approximately 0.75% additional genetic material.

So here's a question worth asking:

Should your child's treatment and supplement regimen be based on that 0.75% alone?

That extra copy of chromosome 21 is important. It can have widespread effects on development, metabolism, immune function, thyroid physiology, neurological function, and much more.

But it isn't the whole story.

The other 99.25% of their genetics matters too.

But genetics is only part of what makes each person unique.

Every person with Down syndrome has a different medical history, diet, nutritional status, environment, medication exposure, microbiome, gut health, immune history, sleep patterns, activity level, and countless other influences that shape how their body functions.

Even two people with the same diagnosis can have remarkably different biochemistry and very different needs.

This is why we believe supplement recommendations for people with Down syndrome are most helpful when we consider the individual as a whole, not simply the diagnosis.

Chromosome 21 should inform our understanding of a person. It shouldn't become our entire understanding of them.

Look at the whole person. Ask questions. Test when appropriate. Consider their history, symptoms, diet, environment, and individual biochemistry.

Because a person with Down syndrome is so much more than their extra chromosome.

www.peirsoncenter.com

07/25/2026

Concerns About Long-Term Miralax Use in Children

🧠 Behavioral and neurologic concerns

The FDA has received reports from families describing behavioral and neuropsychiatric changes in children taking PEG 3350, including anxiety, aggression, mood changes, obsessive-compulsive behaviors, tics, and sleep disturbances. Importantly, these reports do not prove that Miralax caused these symptoms, and studies have not established a causal relationship. However, the reports were significant enough that the FDA called for additional research into the long-term safety of PEG 3350 in children.

FDA Briefing Document on Polyethylene Glycol (PEG 3350) Safety:
https://www.accessdata.fda.gov/drugsatfda_docs/nda/2013/203595Orig1s000OtherR.pdf (opens as PDF)

🛡️ It may temporarily disrupt the gut's protective mucosal layer and have lasting effects on the microbiome

Animal studies have shown that PEG treatment can temporarily disrupt the intestine's protective mucus barrier, resulting in a thinner mucus layer, sometimes with areas of complete mucus loss, and allowing bacteria to come into direct contact with the intestinal epithelium. In these studies, the mucus layer recovered within a few days after PEG was discontinued, but the findings demonstrate that PEG can transiently alter the intestinal environment rather than acting as a completely inert stool softener.

Transient osmotic perturbation causes long-term alteration to the gut microbiota
https://pmc.ncbi.nlm.nih.gov/articles/PMC6061967/

🔍 It doesn't address the root cause

Miralax softens stool, but it does not correct why constipation developed in the first place. If a child requires Miralax daily for months or even years, it's worth asking what is preventing normal bowel function.

Some of the most common contributors to chronic constipation include:

• Thyroid dysfunction
• Nutrient deficiencies (especially magnesium, vitamin B1, B2, and B6)
• Gut dysbiosis or methane-producing organisms that slow intestinal motility
• Food sensitivities (especially dairy) or chronic intestinal inflammation
• Low muscle tone
• Inadequate hydration or poor dietary fiber intake

Rather than simply making stools softer, the best long-term approach is to identify and address the underlying cause of impaired gut motility. Depending on the child, this may include optimizing thyroid function, correcting nutritional deficiencies, restoring a healthy gut microbiome, treating intestinal dysbiosis when present, improving diet and hydration, and supporting the body's natural motility mechanisms.

Get help for your child here: www.peirsoncenter.com

This post is for educational purposes only and is not medical advice. Never stop or change a prescribed medication without discussing it with your child's healthcare provider.

07/16/2026

We're excited to announce that Dr. Erica Peirson will be speaking at the MAPS Functional & Translational Medicine Conference this September 10-12 in Philadelphia!

Last week, MAPS featured Dr. Peirson's upcoming case presentation of a 22-year-old woman with Down syndrome whose regression-like symptoms initially appeared consistent with Down Syndrome Regression Disorder (DSRD). A deeper investigation, however, uncovered folate receptor autoimmunity alongside significant gastrointestinal dysbiosis and multiple nutritional deficiencies, demonstrating how several interconnected biological factors were contributing to her neurological and behavioral symptoms.

As a bonus, Dr. Peirson will also share the case of a young man with Down syndrome who developed similar regression-like symptoms but experienced a much more rapid recovery after a focused evaluation identified a handful of key, treatable contributors. His case demonstrates that recovery is possible when the root causes of regression are recognized and addressed.

These cases highlight an important principle that guides our practice every day: looking beyond diagnostic labels to identify the underlying biological mechanisms affecting health.

During this session, attendees will learn:

• The overlap between Down syndrome regression and cerebral folate autoimmunity
• When Folate Receptor Antibody (FRAT) testing should be considered
• The role of folinic acid therapy in complex neurobehavioral presentations
• Integrative strategies to restore gastrointestinal function, nutrient status, immune health, and microbiome balance

The MAPS Conference is one of the premier educational events in functional and integrative medicine, bringing together world-class speakers to share practical, evidence-informed strategies that clinicians can immediately apply in practice. Whether you're a physician, nurse practitioner, physician assistant, naturopathic physician, nutritionist, therapist, or another healthcare professional, the conference offers an incredible opportunity to learn from leaders across many specialties.

Practitioners can register here:

https://conference.medmaps.org/c/9953b701-0174-4664-b455-b1ca6d9aa7f8

When registering, use your discount code:

🎉 PEIRSON20 for 20% off conference registration.

The conference will be held:

September 10–12, 2026
Philadelphia Marriott Downtown

We hope to see many of you in Philadelphia this September!

06/18/2026

Dr. Peirson was honored to be mentioned by Elliott Overton in this video. His educational content has been an invaluable resource and has helped shape Dr. Peirson's understanding of thiamine metabolism and its potential role in neurodevelopment.

One reason Elliott and Dr. Peirson find themselves on the same page about thiamine is that they have both heard remarkable stories from families who have seen meaningful gains in speech, energy, attention, and engagement after addressing thiamine insufficiency or dysfunction. While thiamine is certainly not the answer for everyone, for some children it appears to have influenced their trajectory of development in profound ways.

Dr. Peirson is grateful for the opportunity to continue learning from colleagues around the world who share a curiosity about metabolism, neurodevelopment, and how to better support individuals and families still searching for answers.

06/17/2026

Creatine isn't just for muscles.

Three studies over the past two decades have found that creatine supplementation can help preserve cognitive performance during periods of sleep deprivation. Participants taking creatine performed better on tasks involving memory, processing speed, attention, logical reasoning, and executive function compared with those receiving placebo. In one study, researchers were even able to demonstrate increases in the brain's high-energy phosphates (ATP and phosphocreatine) and prevention of the drop in brain pH that normally accompanies sleep loss.

Effect of creatine supplementation and sleep deprivation, with mild exercise, on cognitive and psychomotor performance, mood state, and plasma concentrations of catecholamines and cortisol
https://pubmed.ncbi.nlm.nih.gov/16416332/

Single-Dose Creatine Reduces Sleep Deprivation-Induced Deterioration in Cognitive Performance
https://pubmed.ncbi.nlm.nih.gov/42075005/

Single dose creatine improves cognitive performance and induces changes in cerebral high energy phosphates during sleep deprivation
https://pmc.ncbi.nlm.nih.gov/articles/PMC10902318/

Why might this be relevant for those with Down syndrome?

Sleep disruption is extremely common in Down syndrome. Differences in airway anatomy, low muscle tone, and a high prevalence of obstructive sleep apnea can lead to fragmented sleep, intermittent hypoxia, and chronic sleep deprivation.

At the same time, several studies suggest that individuals with Down syndrome may have reduced mitochondrial efficiency and increased oxidative stress, placing greater demands on cellular energy production.

Creatine is also interesting from a biochemical perspective. The body's own production of creatine is surprisingly expensive from a methylation standpoint, consuming a substantial proportion of available methyl groups. Methylation pathways have been shown to be altered in Down syndrome, raising the possibility that some individuals may have difficulty keeping up with creatine demands through endogenous synthesis alone.

Creatine acts as a rapid energy reserve, helping regenerate ATP when demand is high. The available studies suggest that its cognitive benefits may be most apparent when the brain is under stress, such as during sleep deprivation.

Creatine has not been studied specifically in Down syndrome for this purpose, so we cannot assume it will provide the same benefits. Still, given the combination of altered methylation, mitochondrial differences, and the high burden of sleep disruption in this population, creatine supplementation may be an interesting proposition worthy of further study.

www.peirsoncenter.com

06/15/2026

A special announcement from the Peirson Center for Children 💙💛

The Peirson Center will be closed from June 23 through July 8 while Dr. Peirson, Stephen, and Miles take a family vacation.

Many of you have followed Miles' journey over the years. From a little boy with big dreams to a young man who recently graduated from high school with honors and is preparing to begin his next chapter at Boise State University, it has been an incredible journey to witness.

Before Miles begins college, our family is taking the opportunity to spend some quality time together and create a few more memories before this exciting transition.

During this time:
• Dr. LaRosa and Dr. Ast will be unavailable June 21 through June 27.
• Dr. Ast and Dr. LaRosa will resume seeing patients beginning June 29 and will continue seeing patients through July 7.
• Dr. Peirson will not be routinely monitoring messages while away.
• Messages requiring Dr. Peirson's review will be addressed after the office reopens on July 9.

If you need prescription refills, lab-related questions, supplement guidance, or other non-urgent assistance, please contact the office before June 20 whenever possible.

Thank you for your understanding and for allowing the Peirson Center to be part of your family's journey. We are grateful for this community and look forward to returning refreshed and ready to continue serving your children.

See you in July!

06/11/2026

Crossed eyes are not just part of Down syndrome.

Yes, strabismus (crossed eyes) is more common in individuals with Down syndrome.

But when a child's eye turns inward, we should be asking an important question:

Why is the eye turning inward?

In some cases, the problem may not be the eye itself. The problem may be a weak nerve.

The muscle that pulls the eye outward toward the ear is called the lateral re**us muscle. This muscle is controlled by the sixth cranial nerve, also known as the abducens nerve.

When that nerve becomes weak or damaged, the eye cannot move outward normally. The stronger muscles that pull the eye inward toward the nose gradually win the tug-of-war, causing the eye to drift inward.

In other words, crossed eyes can sometimes be a sign of a neurological problem rather than simply an eye alignment problem.

One of the most well-established nutritional causes of eye movement abnormalities is thiamine (vitamin B1) deficiency. Thiamine deficiency can cause ophthalmoplegia (paralysis or weakness of the eye muscles), nystagmus, and dysfunction of the cranial nerves that control eye movement.

Deficiencies of vitamin B12 and vitamin B6 can also contribute to nerve dysfunction and have been associated with cranial neuropathies affecting eye movement.

To be clear, not every child with strabismus has a vitamin deficiency. There are many possible causes.

But before we assume that crossed eyes are simply "part of Down syndrome," we should consider whether there is an underlying nutritional or neurological reason the eye muscles are not working properly.

A patch may help strengthen visual development.

Surgery may improve alignment.

But neither addresses a nutrient deficiency if that deficiency is contributing to the nerve weakness in the first place.

When we see crossed eyes, we don't just think about the eye.

We think about the nerve controlling the eye.

And we think about whether that nerve has the nutrients it needs to function properly.

References:

• Kumar PD, et al. Unilateral internuclear ophthalmoplegia and recovery with thiamine in Wernicke syndrome. PMID: 11061354.
https://pubmed.ncbi.nlm.nih.gov/11061354/

• Wernicke Encephalopathy (StatPearls): Thiamine deficiency is classically associated with ophthalmoplegia and abnormal eye movements.
https://www.ncbi.nlm.nih.gov/books/NBK470344/

• EyeWiki: Wernicke Encephalopathy. Ophthalmoplegia is a hallmark manifestation of vitamin B1 deficiency.
https://eyewiki.org/Wernicke_Encephalopathy

• The Effect of Combined Vitamin B Therapy on the Outcome of Diabetic Isolated Abducent Nerve Palsy (conference proceedings).
https://www.longdom.org/proceedings/the-effect-of-combined-vitamin-b-therapy-on-the-outcome-of-diabetic-isolated-abducent-nerve-palsy-53619.html

As always, this post is for educational purposes only and is not intended to diagnose or treat any medical condition.

Peirson Center for Children

08/29/2026

08/25/2026

08/19/2026

08/18/2026

07/25/2026

07/16/2026

06/18/2026

06/17/2026

06/15/2026

06/11/2026

Address

Opening Hours

Telephone

Website

Alerts

Shortcuts

Share

Category

Listing takedown request

Monday	9am - 4pm
Tuesday	9am - 4pm
Wednesday	9am - 4pm
Thursday	9am - 4pm
Friday	9am - 4pm