2024 ICD-10-CM Diagnosis Code E21.5

Approximate Synonyms

The following clinical terms are approximate synonyms or lay terms that might be used to identify the correct diagnosis code:

• Anemia of endocrine disorder
• Anemia of parathyroid dysfunction
• Disorder of parathyroid gland
• Polyneuropathy due to disorder of parathyroid gland

Diagnostic Related Groups - MS-DRG Mapping

Diagnostic Related Groups (DRGs) are a classification system used to group together diagnosis codes for the purpose of reimbursement and healthcare management. DRGs are used to standardize the way hospitals and other providers are paid for inpatient services. In this system patients are grouped together based on their principal diagnosis in areas referred to as Major Diagnostic Categories (MDC). Once a patient is assigned a particular diagnostic category, providers receive a predetermined payment rate for the services rendered. This reimbursement rate is often fixed and is meant to cover the cost of care for that patient. Reimbursement is also affected by the relative weight of a diagnostic related group based on the severity of a patient's illness and the associated cost of care during hospitalization.

Diagnostic related groups encourage healthcare providers to focus on quality and efficiency in patient care while managing costs effectively. The diagnosis code is present in the following groups for version MS-DRG V41.0 applicable from 10/01/2023 through 09/30/2024.

MS-DRG	MS-DRG Title	MCD	Relative Weight
643	ENDOCRINE DISORDERS WITH MCC	10	1.6451
644	ENDOCRINE DISORDERS WITH CC	10	1.0617
645	ENDOCRINE DISORDERS WITHOUT CC/MCC	10	0.7609

The relative weight of a diagnostic related group determines the reimbursement rate based on the severity of a patient's illness and the associated cost of care during hospitalization.

Convert to ICD-9-CM Code

Source ICD-10-CM Code		Target ICD-9-CM Code
E21.5		252.9 - Parathyroid disorder NOS

Patient Education

Parathyroid Disorders

Most people have four pea-sized glands, called parathyroid glands, on the thyroid gland in the neck. Though their names are similar, the thyroid and parathyroid glands are completely different. The parathyroid glands make parathyroid hormone (PTH), which helps your body keep the right balance of calcium and phosphorous.

If your parathyroid glands make too much or too little hormone, it disrupts this balance. If they secrete extra PTH, you have hyperparathyroidism, and your blood calcium rises. In many cases, a benign tumor on a parathyroid gland makes it overactive. Or, the extra hormones can come from enlarged parathyroid glands. Very rarely, the cause is cancer.

If you do not have enough PTH, you have hypoparathyroidism. Your blood will have too little calcium and too much phosphorous. Causes include injury to the glands, endocrine disorders, or genetic conditions. Treatment is aimed at restoring the balance of calcium and phosphorous.

NIH: National Institute of Diabetes and Digestive and Kidney Diseases

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Code History

• FY 2024 - No Change, effective from 10/1/2023 through 9/30/2024
• FY 2023 - No Change, effective from 10/1/2022 through 9/30/2023
• FY 2022 - No Change, effective from 10/1/2021 through 9/30/2022
• FY 2021 - No Change, effective from 10/1/2020 through 9/30/2021
• FY 2020 - No Change, effective from 10/1/2019 through 9/30/2020
• FY 2019 - No Change, effective from 10/1/2018 through 9/30/2019
• FY 2018 - No Change, effective from 10/1/2017 through 9/30/2018
• FY 2017 - No Change, effective from 10/1/2016 through 9/30/2017
• FY 2016 - New Code, effective from 10/1/2015 through 9/30/2016. This was the first year ICD-10-CM was implemented into the HIPAA code set.