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FADI F SIYAM M.D.
NPI 1558526574
Internal Medicine - Endocrinology, Diabetes & Metabolism in Saint Louis, MO

Active since July 21, 2008PECOS EnrolledAccepts Medicare Assignment
94.61/100
CMS Quality Rating
12700 SOUTHFORK RD STE 205, SAINT LOUIS, MO 63128(314) 525-7350(314) 525-7356 Get Directions Write a Review

NPPES record last updated: February 4, 2025. Verified against the NPPES registry weekly; last sync: October 25, 2026.

Record update history: Feb 4, 2025, Jun 26, 2024, Jun 20, 2024 and 4 more (7 updates tracked since 2019).

About Fadi F Siyam M.d. NPPES

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

FADI F SIYAM M.D. (NPI 1558526574) is an individual endocrinology, diabetes & metabolism provider in Saint Louis, Missouri, licensed in Missouri (2013002833) and active in the NPI registry since July 2008. He is enrolled in Medicare PECOS, is affiliated with Mercy Hospital St Louis, and is a graduate of Other (2005).

NPPES Registry Identity

NPI1558526574
Entity TypeIndividualMale
Primary Taxonomy207RE0101X
Provider Legal NameFADI F SIYAMCredential: M.D.
Location Address12700 SOUTHFORK RD STE 205Saint Louis, MO 63128-3201
Mailing Address12700 Southfork Rd Ste 205Saint Louis, MO 63128-3201 · (314) 525-7350 · Fax (314) 525-7356
Phone(314) 525-7350
Fax(314) 525-7356
Sole ProprietorNo
Medical School CMSOtherGraduated 2005
Enumeration DateJuly 21, 2008
Last NPPES UpdateFebruary 4, 20257 updates tracked since enumeration
NPPES CertifiedFebruary 4, 2025
✔ NPI 1558526574 is a valid, active identifier and passes the ISO check-digit test.

Specialties & Licenses

★ Primary SpecialtyInternal Medicine · Endocrinology, Diabetes & MetabolismAllopathic & Osteopathic Physicians
Taxonomy Code207RE0101X
Licenses✔ Licensed in MO · 2013002833✔ Licensed in OR · MD220356✔ Licensed in IL · 036150752
Definition
An internist who concentrates on disorders of the internal (endocrine) glands such as the thyroid and adrenal glands. This specialist also deals with disorders such as diabetes, metabolic and nutritional disorders, obesity, pituitary diseases and menstrual and sexual problems.
12700 SOUTHFORK RD STE 205, Saint Louis, MO 63128
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Accepted Insurance

The full list of accepted plans is on the Insurance tab. Issuers include Anthem Blue Cross and Blue Shield, UnitedHealthcare.Insurance ›

Medicare Participation & PECOS CMS

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

Medicare Enrollment Status

✔

Enrolled in Medicare and accepts Medicare assignment

Fadi F Siyam M.d. is registered in PECOS and agrees to accept the Medicare-approved amount as full payment. Medicare patients are not billed beyond the standard deductible and coinsurance.

PECOS PAC ID143459420
PECOS Enrollment IDI20140207000856
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

2

Medicare enrollment records show Fadi Siyam reassigns Medicare billing to 2 organizations. Each organization bills Medicare for the services this provider delivers there; the nearest is listed first.

Mercy Clinic Endocrinology, LLC
12 mi
Endocrinology, Diabetes & Metabolism
621 S NEW BALLAS RD, SUITE 460-A
Saint Louis, MO 63141
  • Reassigned Medicare billing, Missouri enrollment
  • 7 clinicians in this Medicare group
NPI 1922328442 (314) 251-4330
Sjl Health Systems Inc
92 mi
Skilled Nursing Facility
900 S CHESTNUT ST
Pana, IL 62557
  • Reassigned Medicare billing, Illinois enrollment
  • Medicare enrollment name: Hshs Medical Group Inc
  • 317 clinicians in this Medicare group
NPI 1215037353 (217) 562-3996

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

Areas of Expertise CMS Part B claims 3

Services this provider delivered to Medicare fee-for-service patients, from the CMS Medicare utilization data. Higher counts generally reflect more experience with a service; care delivered outside Medicare is not included.

Established patient office or other outpatient visit with moderate level of decision making, if using time, 30 minutes or more 99214
This is a routine check-up for patients who have previously visited our clinic. It involves a comprehensive review of your health and any ongoing treatments. The consultation lasts between 30-39 minutes, allowing enough time to discuss any concerns.
67 services54 patients
New patient office or other outpatient visit with moderate level of medical decision making, if using time, 45 minutes or more 99204
This is a first-time office or outpatient visit lasting between 45-59 minutes. The healthcare provider evaluates your health, discusses your medical history, and may suggest further tests or treatments. It's an opportunity to ask questions and understand your health better.
15 services15 patients
Established patient office or other outpatient visit with moderate level of decision making, if using time, 30 minutes or more 99214
This is a routine check-up for patients who have previously visited our clinic. It involves a comprehensive review of your health and any ongoing treatments. The consultation lasts between 30-39 minutes, allowing enough time to discuss any concerns.
14 services14 patients

Hospital Affiliations CMS Care Compare 4

Hospitals where this provider delivers care, identified from recent Medicare claims and place-of-service records.

Mercy Hospital St Louis

Acute Care Hospitals · Saint Louis, MO
4/5 CMS rating
OwnershipVoluntary non-profit - Private
CMS Certification Number260020
Location615 New Ballas RoadSaint Louis, MO 63141 · St. Louis County
Emergency services Birthing friendly

Mercy Hospital Jefferson

Acute Care Hospitals · Festus, MO
3/5 CMS rating
OwnershipVoluntary non-profit - Private
CMS Certification Number260023
Location1400 Us Highway 61Festus, MO 63028 · Jefferson County
Emergency services

Mercy Hospital Washington

Acute Care Hospitals · Washington, MO
4/5 CMS rating
OwnershipVoluntary non-profit - Private
CMS Certification Number260052
Location901 East 5th StreetWashington, MO 63090 · Franklin County
Emergency services

Mercy Hospital South

Acute Care Hospitals · Saint Louis, MO
3/5 CMS rating
OwnershipVoluntary non-profit - Private
CMS Certification Number260077
Location10010 Kennerly RoadSaint Louis, MO 63128 · St. Louis County
Emergency services

Physician Visit Costs CMS claims · ZIP area

Typical Medicare office-visit costs in the 63128 ZIP code area, from fee-for-service claims. These are area statistics, not this provider’s prices; actual charges vary by service and coverage.

New Patient
$128.28 typical visit price
range $55.65 – $169.38
Typical copayment $32.07 (range $13.91 – $42.34)
Most-billed visit code 99204
Established Patient
$98.37 typical visit price
range $17.76 – $137.92
Typical copayment $24.59 (range $4.44 – $34.48)
Most-billed visit code 99214
Amounts reflect what Medicare beneficiaries in this ZIP area are typically charged for office visits. Patients with other coverage should check their individual plans.

Medicare Quality Performance CMS QPP · MIPS

Performance in the CMS Quality Payment Program: the MIPS final score across four weighted categories, and the individual quality measures reported to Medicare.

94.61/100
MIPS Final ScoreMerit-based Incentive Payment System · CMS Quality Payment Program
Scored through an Alternative Payment Model
Quality85.17
Promoting Interoperability100
Improvement Activities40

Referred Medical Equipment & Supplies CMS DME claims 6

Durable medical equipment, devices and supplies this provider ordered from DME suppliers for patients, from Medicare fee-for-service claims.

Supplies for external insulin infusion pump, syringe type cartridge, sterile, each A4225
DME-Other DME · category DE017N
4 suppliers11 claims345 services$2.35 avg. paid by Medicare
Blood glucose test or reagent strips for home blood glucose monitor, per 50 strips A4253
DME-Other DME · category DE017N
26 suppliers74 claims288 services$6.00 avg. paid by Medicare
Lancets, per box of 100 A4259
DME-Medical/Surgical Supplies · category DA000N
13 suppliers18 claims30 services$0.90 avg. paid by Medicare
Insulin for administration through dme (i.e., insulin pump) per 50 units J1817
Treatment-Injections and Infusions (nononcologic) · category RI000N
5 suppliers11 claims1,220 services$6.88 avg. paid by Medicare
Supply allowance for therapeutic continuous glucose monitor (cgm), includes all supplies and accessories, 1 month supply = 1 unit of service K0553
DME-Other DME · category DE017N
20 suppliers373 claims375 services$183.78 avg. paid by Medicare
Receiver (monitor), dedicated, for use with therapeutic glucose continuous monitor system K0554
DME-Other DME · category DE017N
5 suppliers13 claims13 services$197.45 avg. paid by Medicare
Dollar amounts are the average Medicare paid the supplier per service. They are not the cost to the patient.

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 Fadi Siyam's NPI number?

The NPI number for Fadi Siyam is 1558526574. It was assigned to this individual provider in the NPPES registry on July 21, 2008.

Where is Fadi Siyam located?

Fadi Siyam practices at 12700 Southfork Rd Ste 205, Saint Louis, MO 63128. The listed phone number is (314) 525-7350.

What is Fadi Siyam's specialty?

The primary specialty registered for this NPI is Internal Medicine, specializing in Endocrinology, Diabetes & Metabolism, with taxonomy code 207RE0101X.

Is Fadi Siyam enrolled in Medicare?

Yes. Fadi Siyam is registered in the Medicare PECOS system and accepts Medicare assignment, which means accepting the Medicare-approved amount as payment in full for covered services.

Which organizations bill Medicare for Fadi Siyam's services?

According to the CMS Revalidation Reassignment List (October 2026 release), Fadi Siyam reassigns Medicare benefits to 2 organizations: Mercy Clinic Endocrinology, LLC (Saint Louis, MO) and Sjl Health Systems Inc (Pana, IL). 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 Fadi Siyam's services. Reassignment records can lag staffing changes; confirm current arrangements with the organization.

What insurance does Fadi Siyam accept?

Health plans from Anthem Blue Cross and Blue Shield and UnitedHealthcare list Fadi Siyam as in-network in at least one marketplace plan. Coverage varies by plan and year; verify with the insurer or the provider before a visit.

Is Fadi Siyam affiliated with any hospitals?

According to CMS data, Fadi Siyam is affiliated with Mercy Hospital St Louis, Mercy Hospital Jefferson, Mercy Hospital Washington and Mercy Hospital South.

When was this NPI record last updated?

The NPPES record for Fadi Siyam was last updated on February 4, 2025. NPI Profile syncs weekly with the NPPES registry data releases published by CMS. This NPI record was last updated 20 months 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.