SIAM OOTTAMASATHIEN MD
NPI 1215084017
Urology - Pediatric Urology in Boston, MA

Q: What is Siam Oottamasathien's NPI number?

The NPI number for Siam Oottamasathien is 1215084017. It was assigned to this individual provider in the NPPES registry on January 4, 2007.

Q: What is Siam Oottamasathien's specialty?

The primary specialty registered for this NPI is Urology, specializing in Pediatric Urology, with taxonomy code 2088P0231X.

Active since January 04, 2007PECOS Enrolled

55 FRUIT ST, BOSTON, MA 02114(617) 724-0327 Get Directions Write a Review

NPPES record last updated: December 5, 2017. Verified against the NPPES registry weekly; last sync: November 01, 2026.

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About Siam Oottamasathien Md NPPES

Official registry information on file with the National Plan and Provider Enumeration System.

SIAM OOTTAMASATHIEN MD (NPI 1215084017) is an individual pediatric urology provider in Boston, Massachusetts, licensed in Utah (6513463-1205) and active in the NPI registry since January 2007. He is enrolled in Medicare PECOS and is a graduate of University Of Colorado School Of Medicine, Denver (1999).

NPPES Registry Identity

NPI1215084017

Entity TypeIndividualMale

Primary Taxonomy2088P0231X

Provider Legal NameSIAM OOTTAMASATHIENCredential: MD

Location Address55 FRUIT STBoston, MA 02114-2621

Mailing Address55 Fruit StBoston, MA 02114-2621 · (617) 724-0327

Phone(617) 724-0327

Sole ProprietorNo

Medical School CMSUniversity Of Colorado School Of Medicine, DenverGraduated 1999

Enumeration DateJanuary 4, 2007

Last NPPES UpdateDecember 5, 2017

✔ NPI 1215084017 is a valid, active identifier and passes the ISO check-digit test.

Specialties & Licenses 2

★ Primary SpecialtyUrology · Pediatric UrologyAllopathic & Osteopathic Physicians

Taxonomy Code2088P0231X

License✔ Licensed in UT · 6513463-1205

Definition

Surgeons who can diagnose, treat, and manage children's urinary and genital problems. A pediatric urologist devotes a minimum of 50% of his or her practice to the urologic problems of infants, children, and adolescents. Pediatric urologists generally provide the following services: the evaluation and management of voiding disorders; vesicoureteral reflux, and urinary tract infections that require surgery; surgical reconstruction of the urinary tract (kidneys, ureters, and bladder) including genital abnormalities, hypospadias, and intersex conditions; surgery for groin conditions in childhood and adolescence (undescended testes, hydrocele/hernia, varicocele).

Also ListedUrologyTaxonomy 208800000X · License 6513463-1205 (UT)

55 FRUIT ST, Boston, MA 02114

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Medicare Participation & PECOS CMS

Medicare enrollment, assignment, billing reassignment, and ordering and referring status from CMS.

Medicare Enrollment Status

✔

Enrolled in Medicare (PECOS)

Siam Oottamasathien Md is registered in the CMS Provider Enrollment, Chain and Ownership System (PECOS).

PECOS PAC ID42304107

PECOS Enrollment IDI20180115000406

Eligible to Order & Refer✔ Part B Labs & Imaging✔ Durable Medical Equipment✔ Home Health Agency✔ Power Mobility DevicesPer the CMS Ordering and Referring file. Eligibility means Medicare pays claims that this provider orders or refers for these categories.

Medicare Billing Reassignments

Medicare enrollment records show Siam Oottamasathien reassigns Medicare billing to 4 organizations. Each organization bills Medicare for the services this provider delivers there; the nearest is listed first.

Massachusetts General Physicians Organization Inc

Same address

Dermatology

55 FRUIT ST, BUL 2
Boston, MA 02114

Reassigned Medicare billing, Massachusetts enrollment
6,360 clinicians in this Medicare group

NPI 1801874573 (617) 724-0287

The General Hospital Corporation

Same address

General Acute Care Hospital

55 FRUIT ST, BULFINCH 360
Boston, MA 02114

Reassigned Medicare billing, Massachusetts enrollment
6,234 clinicians in this Medicare group

NPI 1023049236 (617) 726-2000

Pratt Urology Associates, Inc

1.0 mi

Urology

800 WASHINGTON ST, BOX 1013
Boston, MA 02111

Reassigned Medicare billing, Massachusetts enrollment
10 clinicians in this Medicare group

NPI 1497795025 (617) 636-5000

Children's Urological Foundation

2.6 mi

Urology

300 LONGWOOD AVE
Boston, MA 02115

Reassigned Medicare billing, Massachusetts enrollment
39 clinicians in this Medicare group

NPI 1144234055 (617) 355-6136

Source: CMS Revalidation Reassignment List, October 2026 release. Reassignment records can lag staffing changes; confirm a current affiliation with the organization.

Other Providers at the Same Location NPPES 20

Providers registered at the same practice address, or within the immediate area, according to the NPPES registry.

STUTI GIRISH SHROFF MD, MBBS

Pathology (Anatomic Pathology)

55 FRUIT ST
BOSTON, MA 02114

Suffolk County (617) 726-2971

NANCY WANG M.D.

Internal Medicine (Hematology & Oncology)

55 FRUIT ST
BOSTON, MA 02114

Suffolk County (017) 724-4000

DR. DUSAN HANIDZIAR M.D., PH.D.

Anesthesiology

55 FRUIT ST, GRAY-BIGELOW 444
BOSTON, MA 02114

Suffolk County (617) 726-3030

JOHN JOSEPH DANKO DO

Physical Medicine & Rehabilitation

55 FRUIT ST
BOSTON, MA 02114

Suffolk County (617) 726-2000

DR. MICHAEL ANDREW LOBRITZ M.D, PH.D.

Internal Medicine (Infectious Disease)

55 FRUIT ST, DIVISION OF INFECTIOUS DISEASE, GRJ-504
BOSTON, MA 02114

Suffolk County (617) 724-9248

MS. KELLY ELISHA TRECARTIN NP

Nurse Practitioner (Acute Care)

55 FRUIT ST, BIGALOW 852 F
BOSTON, MA 02114

Suffolk County (617) 726-7400

JAMIE MARIE ALLEN NP

Nurse Practitioner

55 FRUIT ST
BOSTON, MA 02114

Suffolk County (617) 724-4410

DR. DHAVAL SANJEEV KOLTE M.B.B.S., PH.D.

Internal Medicine (Cardiovascular Disease)

55 FRUIT ST
BOSTON, MA 02114

Suffolk County (617) 643-3238

Frequently Asked Questions NPPES & CMS

Common questions about this NPI record, answered from the official NPPES registry and CMS datasets shown on this page.

What is Siam Oottamasathien's NPI number?

The NPI number for Siam Oottamasathien is 1215084017. It was assigned to this individual provider in the NPPES registry on January 4, 2007.

Where is Siam Oottamasathien located?

Siam Oottamasathien practices at 55 Fruit St, Boston, MA 02114. The listed phone number is (617) 724-0327.

What is Siam Oottamasathien's specialty?

The primary specialty registered for this NPI is Urology, specializing in Pediatric Urology, with taxonomy code 2088P0231X.

Is Siam Oottamasathien enrolled in Medicare?

Yes. Siam Oottamasathien is registered in the Medicare PECOS enrollment system.

Which organizations bill Medicare for Siam Oottamasathien's services?

According to the CMS Revalidation Reassignment List (October 2026 release), Siam Oottamasathien reassigns Medicare benefits to 4 organizations: Massachusetts General Physicians Organization Inc (Boston, MA), The General Hospital Corporation (Boston, MA), Pratt Urology Associates, Inc (Boston, MA) and Children's Urological Foundation (Boston, MA). Each reassignment is filed with Medicare on form CMS-855R, signed by both the clinician and the organization, and lets the organization bill Medicare and receive payment for Siam Oottamasathien's services. Reassignment records can lag staffing changes; confirm current arrangements with the organization.

When was this NPI record last updated?

The NPPES record for Siam Oottamasathien was last updated on December 5, 2017. NPI Profile syncs weekly with the NPPES registry data releases published by CMS. This NPI record was last updated 8 years ago. If this record has changed at CMS more recently, you can request an on-demand re-check against the live CMS registry, directly from this page.