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Dr. Mark Urtal Liong, M.D.

Nephrology Physician in Mcallen, TX · enumerated 2007 · practices at South Texas Kidney Specialists, P.A..

Data current as of Jul 13, 2026 · sourced from CMS NPPES

National Provider Identifier

1346422078

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Registry record

Entity type Individual (Type 1)
Name Dr. Mark Urtal Liong
Credential M.D.
Sex Male
Practice address 1901 S 1st St Ste 600, Mcallen, TX, 78503
Phone (956) 631-6136
Fax (956) 631-1848
Enumeration date Dec 5, 2007
Last updated in NPPES Jan 8, 2015

Taxonomy & licenses

207RN0300X Nephrology Physician Allopathic & Osteopathic Physicians · License P4673 (TX) Primary
MD · Doctor of Medicine: A physician who completed medical school (allopathic medicine), residency training, and state licensure. About the MD credential

Other identifiers

Identifier Type State Issuer
334541501 Medicaid TX -

What is an NPI number?

A National Provider Identifier (NPI) is a unique 10-digit number that CMS assigns to every U.S. healthcare provider and organization under HIPAA. Type 1 NPIs identify individual providers; Type 2 NPIs identify organizations. The NPI appears on insurance claims, prescriptions, and credentialing paperwork, and never changes, even if the provider moves or changes specialty.

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Frequently asked questions

What is the NPI number for Mark Liong?
The National Provider Identifier (NPI) for Mark Liong is 1346422078, a Type 1 (individual) record in the CMS NPPES registry.
Where does Mark Liong practice?
The practice location on file with NPPES is in Mcallen, TX. Providers can have multiple locations; NPPES lists the primary practice address.

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Source: CMS NPPES (public data). Snapshot 2026-07-13. Provider record last updated 2015-01-08.