MS-DRG 596 – Major Skin Disorders without MCC
A Medical DRG in MDC 09 (Diseases & Disorders of the Skin, Subcutaneous Tissue & Breast). Inpatient cases group to DRG 596 when the ICD-10-CM principal diagnosis is one of the 115 codes listed below and no secondary diagnosis on the MCC list is present. Its FY 2026 relative weight is 1.0825 with a geometric mean length of stay of 3.4 days.
Severity family
The grouper first assigns the case to MDC 09 from the principal diagnosis and finds no qualifying operating-room procedure (this is a Medical DRG; ICD-10-PCS codes do not drive assignment here), then applies the severity split from secondary diagnoses: with MCC → 595; without MCC → 596.
Principal Diagnosis Codes 115 codes · 17 categories
B02 Zoster [herpes zoster]1 code
- B02.9 Zoster without complications
C43 Malignant melanoma of skin19 codes
- C43.0 Malignant melanoma of lip
- C43.20 Malignant melanoma of unspecified ear and external auricular canal
- C43.21 Malignant melanoma of right ear and external auricular canal
- C43.22 Malignant melanoma of left ear and external auricular canal
- C43.30 Malignant melanoma of unspecified part of face
- C43.31 Malignant melanoma of nose
- C43.39 Malignant melanoma of other parts of face
- C43.4 Malignant melanoma of scalp and neck
- C43.51 Malignant melanoma of anal skin
- C43.52 Malignant melanoma of skin of breast
- C43.59 Malignant melanoma of other part of trunk
- C43.60 Malignant melanoma of unspecified upper limb, including shoulder
- C43.61 Malignant melanoma of right upper limb, including shoulder
- C43.62 Malignant melanoma of left upper limb, including shoulder
- C43.70 Malignant melanoma of unspecified lower limb, including hip
- C43.71 Malignant melanoma of right lower limb, including hip
- C43.72 Malignant melanoma of left lower limb, including hip
- C43.8 Malignant melanoma of overlapping sites of skin
- C43.9 Malignant melanoma of skin, unspecified
C4A Merkel cell carcinoma24 codes
- C4A.0 Merkel cell carcinoma of lip
- C4A.10 Merkel cell carcinoma of unspecified eyelid, including canthus
- C4A.111 Merkel cell carcinoma of right upper eyelid, including canthus
- C4A.112 Merkel cell carcinoma of right lower eyelid, including canthus
- C4A.121 Merkel cell carcinoma of left upper eyelid, including canthus
- C4A.122 Merkel cell carcinoma of left lower eyelid, including canthus
- C4A.20 Merkel cell carcinoma of unspecified ear and external auricular canal
- C4A.21 Merkel cell carcinoma of right ear and external auricular canal
- C4A.22 Merkel cell carcinoma of left ear and external auricular canal
- C4A.30 Merkel cell carcinoma of unspecified part of face
- C4A.31 Merkel cell carcinoma of nose
- C4A.39 Merkel cell carcinoma of other parts of face
- C4A.4 Merkel cell carcinoma of scalp and neck
- C4A.51 Merkel cell carcinoma of anal skin
- C4A.52 Merkel cell carcinoma of skin of breast
- C4A.59 Merkel cell carcinoma of other part of trunk
- C4A.60 Merkel cell carcinoma of unspecified upper limb, including shoulder
- C4A.61 Merkel cell carcinoma of right upper limb, including shoulder
- C4A.62 Merkel cell carcinoma of left upper limb, including shoulder
- C4A.70 Merkel cell carcinoma of unspecified lower limb, including hip
- C4A.71 Merkel cell carcinoma of right lower limb, including hip
- C4A.72 Merkel cell carcinoma of left lower limb, including hip
- C4A.8 Merkel cell carcinoma of overlapping sites
- C4A.9 Merkel cell carcinoma, unspecified
D03 Melanoma in situ18 codes
- D03.0 Melanoma in situ of lip
- D03.20 Melanoma in situ of unspecified ear and external auricular canal
- D03.21 Melanoma in situ of right ear and external auricular canal
- D03.22 Melanoma in situ of left ear and external auricular canal
- D03.30 Melanoma in situ of unspecified part of face
- D03.39 Melanoma in situ of other parts of face
- D03.4 Melanoma in situ of scalp and neck
- D03.51 Melanoma in situ of anal skin
- D03.52 Melanoma in situ of breast (skin) (soft tissue)
- D03.59 Melanoma in situ of other part of trunk
- D03.60 Melanoma in situ of unspecified upper limb, including shoulder
- D03.61 Melanoma in situ of right upper limb, including shoulder
- D03.62 Melanoma in situ of left upper limb, including shoulder
- D03.70 Melanoma in situ of unspecified lower limb, including hip
- D03.71 Melanoma in situ of right lower limb, including hip
- D03.72 Melanoma in situ of left lower limb, including hip
- D03.8 Melanoma in situ of other sites
- D03.9 Melanoma in situ, unspecified
L00 Staphylococcal scalded skin syndrome1 code
- L00 Staphylococcal scalded skin syndrome
L10 Pemphigus9 codes
L12 Pemphigoid7 codes
L13 Other bullous disorders2 codes
L14 Bullous disorders in diseases classified elsewhere1 code
- L14 Bullous disorders in diseases classified elsewhere
L40 Psoriasis6 codes
L41 Parapsoriasis7 codes
L51 Erythema multiforme6 codes
L52 Erythema nodosum1 code
- L52 Erythema nodosum
L53 Other erythematous conditions4 codes
L93 Lupus erythematosus3 codes
L94 Other localized connective tissue disorders1 code
- L94.5 Poikiloderma vasculare atrophicans
Procedure Codes
Frequently Asked Questions
What is MS-DRG 596?
MS-DRG 596 (Major Skin Disorders without MCC) is a medical DRG in MDC 09 (Diseases & Disorders of the Skin, Subcutaneous Tissue & Breast). Its FY 2026 relative weight is 1.0825 with a geometric mean length of stay of 3.4 days.
What is the difference between DRG 595, 596?
All 2 share the same base category; the severity of secondary diagnoses separates them: 595 (with MCC), 596 (without MCC). A major complication or comorbidity (MCC) places the case in the highest-weighted DRG of the family; a CC in the middle; neither in the lowest.
How many diagnosis codes group to DRG 596?
115 ICD-10-CM principal diagnosis codes group to this DRG, spanning 17 three-character categories.
What is the relative weight of DRG 596?
The FY 2026 relative weight of this DRG is 1.0825, meaning reimbursement of roughly 1.08 times the average Medicare inpatient case. Multiply by a hospital's blended base rate for the approximate payment.
