Doctor profile · Federal record

Dr. William Dierenfeldt, MD

Gastroenterology Physician (CMS: Gastroenterology) · Manhattan, KS

  • NPI 1477591634
  • Accepts Medicare
  • 32 yrs in practice
  • Male
  • Group practice
  • No sanctions

Practice & contact

Operates at 2 locations .

NPPES Updated May 11, 2026
Primary practice
1325 Research Park Dr
Manhattan, KS 665025000
(785) 537-2651
Additional location
1102 Saint Marys RD
Junction City, KS 664414139
(785) 238-0325
fax (785) 576-1113

Credentials & registration

NPPES · NUCC
NPI registered
June 2006 — 20 yrs on file
Profile last updated
January 5, 2026
Year of graduation
1994 — 32 yrs since
Specialty taxonomy
207RG0100X — NUCC code
State license (1)
Kansas #04-28673

Federal sanctions & exclusions

OIG LEIE Updated May 11, 2026

No sanctions, exclusions or revocations on file

Checked against OIG LEIE on NPI 1477591634. Last verified May 11, 2026.

Medicare procedures · 2023

Top services delivered

CMS Provider Utilization
Total services
1,038
Distinct HCPCS
10
Medicare allowed
$152,294
HCPCS Description Services Patients Avg allowed
45385 Removal of polyps or growths of large bowel using an endoscope with mechanical snare 263 260 $230
43239 Biopsy of esophagus, stomach, and/or upper small bowel using a flexible endoscope 252 241 $71
G0105 Colorectal cancer screening; colonoscopy on individual at high risk 120 120 $169
43249 Balloon dilation of esophagus, stomach, and/or upper small bowel using a flexible endoscope, less than 3.0 cm 104 77 $126
45380 Biopsy of large bowel using a flexible endoscope 90 90 $124
G0121 Colorectal cancer screening; colonoscopy on individual not meeting criteria for high risk 57 57 $172
45378 Diagnostic exam of large bowel using a flexible endoscope 45 45 $165
43235 Diagnostic exam of esophagus, stomach, and/or upper small bowel using a flexible endoscope 34 33 $95
99213 Established patient office or other outpatient visit, 20-29 minutes 26 24 $85
99203 New patient office or other outpatient visit, 30-44 minutes 16 16 $105

In context: peer comparison

Among 2 peers in Manhattan Gastroenterology Physician, average services per provider: 65. This provider delivers 16× the peer median.

Medicare Part D · 2023

Top prescriptions

CMS Part D Prescriber
Total claims
749
Patients
138
Total drug cost
$34,414
Drug Type Claims Patients Total cost
Pantoprazole Sodium Generic 397 93 $5,740
Omeprazole Generic 103 32 $1,340
Famotidine Generic 38 0 $293
Nortriptyline Hcl Generic 36 0 $276
Dicyclomine Hcl Generic 25 0 $699
Budesonide Dr (Budesonide) Brand 24 0 $5,473
Sucralfate Generic 21 0 $998
Ondansetron Hcl Generic 17 0 $477
Gavilyte-G (Peg3350/Sod Sulf,Bicarb,Cl/Kcl) Brand 14 13 $239
Azathioprine Generic 13 0 $2,048

Frequently asked questions

Auto-generated from federal data
What is Dr. William Dierenfeldt's medical specialty?
Dr. William Dierenfeldt practices Gastroenterology Physician in Manhattan, KS.
Where does Dr. William Dierenfeldt practice?
Dr. William Dierenfeldt practices at 1325 Research Park Dr, Manhattan, KS 665025000. Office phone: 7855372651.
What is Dr. William Dierenfeldt's NPI?
Dr. William Dierenfeldt's National Provider Identifier (NPI) is 1477591634, issued by NPPES.
Does Dr. William Dierenfeldt accept Medicare assignment?
Yes. Dr. William Dierenfeldt accepts Medicare assignment, meaning Medicare-allowed amounts are accepted as full payment for covered services.
What procedures does Dr. William Dierenfeldt commonly perform?
Top Medicare-reported procedures in 2023: Removal of polyps or growths of large bowel using an endoscope with mechanical snare (HCPCS 45385); Biopsy of esophagus, stomach, and/or upper small bowel using a flexible endoscope (HCPCS 43239); Colorectal cancer screening; colonoscopy on individual at high risk (HCPCS G0105). Source: CMS Medicare Physician & Other Practitioners file.