AutoICD API

R99

Billable

Ill-defined and unknown cause of mortality

Ill-defined and unknown cause of mortality

Status

Billable / Specific

Block

R99-R99

ICD-11 Mapping

1 equivalent

Coding Notes

Inclusion Terms

Alternative clinical terms for this condition

  • Death (unexplained) NOS
  • Unspecified cause of mortality

Excludes 2

Conditions not included here, but the patient may have both

ICD-11 Equivalents(1)

ICD-11 Equivalents

View full mapping

Corresponding ICD-11 codes from the WHO crosswalk mapping

MH14Other ill-defined or unspecified causes of mortalityequivalentPrimary
Also Known As / Clinical Terms(397)

SNOMED CT

UMLS

Clinical Terms

  • Intraoperative or immediately postoperative death in an American Society of Anesthesiologists Class I patient
  • Fetal disorder due to maternal death
  • Late neonatal death
  • Patient status determination, deceased and buried
  • SIDS - sudden infant death syndrome
  • GRACILE syndrome
  • Finnish lactic acidosis with hepatic hemosiderosis
  • Sudden death
  • Sudden death of unknown cause during the puerperium
  • Unexpected sudden death of infant
  • Adverse incident outcome
  • SUDEP - sudden unexpected death in epilepsy
  • Fellman syndrome
  • Serious reportable event associated with environment
  • Died in ambulance
  • Postmortem rigidity
  • Accidental death in home
  • Died in street
  • Died in hospice
  • Ill-defined and unknown cause of mortality (R99)
  • D.O.A.
  • Sudden infant death
  • Died in learning disability unit
  • Serious reportable event associated with patient protection
  • Death associated with influenza
  • Entombment
  • Indirect maternal death
  • Accidental death in public place
  • Accidental death
  • Probable suicide
  • Death
  • Dead - unexpected
  • Death in nursing home
  • Patient death or serious disability associated with an electric shock while being cared for in a healthcare facility
  • Died
  • Death by fire
  • Patient status determination, deceased and removed from state
  • Died in usual place of residence
  • Direct maternal death
  • Eastern Cooperative Oncology Group performance status finding
  • Open verdict
  • Unknown cause of death
  • Died in care home
  • Immolation
  • Cremation
  • Death due to radiotherapy toxicity
  • Sudden death, cause unknown
  • Suspicious death
  • Patient deceased during stay (discharge status = dead)
  • Death from direct obstetric cause occurring more than 42 days but less than one year after delivery
  • Death in hospital
  • Found dead in bed
  • Maternal mortality
  • Found dead at accident site
  • Death, manner undetermined
  • Rigor mortis
  • Anesthetic death
  • Dead - suspicious death
  • Autopsy pending
  • Natural death with suspected cause
  • Autopsy performed
  • Traffic vehicular accidental death
  • Clavien-Dindo classification grade V
  • Non-traffic vehicular accidental death
  • Death of unknown cause (event)
  • Has died
  • Found dead
  • Unwitnessed death
  • Death during anesthetic induction
  • Patient death associated with a fall whilst being cared for in a healthcare facility
  • ECOG performance status - grade 5
  • Anaesthetic death
  • Death by immolation
  • Mortality associated with respiratory syncytial virus infection
  • Death by hanging
  • Eastern Cooperative Oncology Group performance status - grade 5
  • Natural death
  • Perinatal death
  • Unexplained sudden death
  • Killed
  • Maternal death
  • Death due to natural causes
  • Postoperative death
  • Brought in dead
  • Died without sign of disease
  • ECOG performance status finding
  • Natural death reportable to medicolegal authority
  • Death in home
  • Died during operation
  • Death by asphyxiation
  • Patient death associated with a fall while being cared for in a healthcare facility
  • BID - Brought in dead
  • Clavien-Dindo classification finding
  • Death by suffocation
  • Maternal death - perinatal
  • Patient pronounced dead
  • Unexpected sudden death of adult
  • Died in mental health unit
  • Death occurring less than 24 hours from onset of symptoms
  • Death - cause unknown
  • Death due to trampling
  • Antepartum maternal death
  • Unattended death
  • Adverse event outcome
  • Died in community hospital
  • Death in less than 24 hours from onset of symptoms
  • Donation
  • Dead
  • Postpartum maternal death
  • Karoshi
  • Unexpected death
  • Sudden infant death syndrome
  • deaths unexplained
  • Newborn death
  • Dead on arrival at hospital
  • Patient status determination, deceased and body donated
  • Finnish lethal neonatal metabolic syndrome
  • Accidental death in work place
  • Removal from state
  • Patient death or serious disability associated with the use of restraints or bedrails whilst being cared for in a healthcare facility
  • unexplained death
  • Undetermined manner of death, natural causes suspected
  • Death from overwork
  • Undetermined manner of death, suicide suspected
  • Child death
  • Natural death with proved cause without autopsy
  • Perinatal mortality
  • Neonatal death
  • Unspecified cause of mortality
  • Accidentally killed
  • Preoperative anesthetic death
  • Patient status determination, deceased and entombed
  • Death in long term care facility
  • Undetermined manner of death
  • Intrapartum maternal death
  • Patient death or serious disability associated with the use of contaminated drugs, devices, or biologics provided by the healthcare facility
  • Death by Undetermined Cause
  • Patient status determination, deceased
  • Death during anaesthetic induction
  • Natural death with proved cause by autopsy
  • Death from indirect obstetric cause occurring more than 42 days but less than one year after delivery
  • Sudden infant death with dysgenesis of testes syndrome
  • Death unexplained
  • Mortality associated with influenza
  • Instantaneous death
  • Patient death or serious disability associated with an electric shock whilst being cared for in a healthcare facility
  • Intraoperative death
  • Cot death
  • Death by cremation
  • Died in nursing home
  • Natural death with proved cause
  • Death due to chemotherapy toxicity
  • Patient status determination, deceased and body cremated
  • Death of unknown cause
  • Patient death or serious disability associated with a burn incurred from any source whilst being cared for in a healthcare facility
  • Patient death or serious disability associated with the use of restraints or bedrails while being cared for in a healthcare facility
  • Perioperative death
  • Sudden unexpected death in epilepsy
  • Died in general practice premises
  • Growth retardation, amino aciduria, cholestasis, iron overload, lactic acidosis, and early death
  • Unattended death of unknown cause
  • Iatrogenic death
  • Dead - death without witness
  • Accidental death in industrial place
  • Infant death
  • Patient death or serious disability associated with a burn incurred from any source while being cared for in a healthcare facility
  • Death in hospital-based emergency department or outpatient department
  • Adverse incident resulting in death
  • Death unattended by physician
  • Intraoperative or immediately postoperative death in an ASA (American Society of Anesthesiologists) Class I patient
  • Late maternal death
  • Early neonatal death
  • Patient death or serious disability associated with the use or function of a device in patient care, in which the device is used or functions other than as intended
  • Death associated with respiratory syncytial virus infection
  • Death (unexplained) NOS
  • Preoperative anaesthetic death
  • Dead - expected
  • Died at home
  • Postmortem plain X-ray abnormal
  • Dead - sudden death
  • Found dead (cause undetermined)
  • Death in residence
  • Postneonatal death
  • Death from sequela of direct obstetric cause
  • Natural death with unknown cause
  • PND - Perinatal death
  • Death from sequela of indirect maternal cause
  • Serious reportable event associated with product or device
  • Natural death with probable cause suspected
  • Death in hospital-based outpatient department
  • Death in nursing home or long term care facility
  • Died in hospital
  • Crib death
  • Death in hospice
  • Patient death or serious disability associated with patient elopement (disappearance) for more than four hours
  • Death in hospital-based emergency department
Frequently Asked Questions
What is the ICD-10 code for ill-defined and unknown cause of mortality?

The ICD-10-CM code for ill-defined and unknown cause of mortality is R99. The full clinical description is "Ill-defined and unknown cause of mortality". R99 is a billable/specific code that can be used on insurance claims and medical billing.

What does ICD-10 code R99 mean?

ICD-10-CM code R99 represents “Ill-defined and unknown cause of mortality”. It is classified under Chapter 18: Symptoms, Signs and Abnormal Clinical and Laboratory Findings and is a billable/specific code that can be used on a claim.

Is R99 a billable code?

Yes, R99 is a billable/specific ICD-10-CM code and can be used to indicate a diagnosis on a medical claim.

What chapter is R99 in?

R99 is in Chapter 18: Symptoms, Signs and Abnormal Clinical and Laboratory Findings (codes R00-R99).

What SNOMED CT codes does R99 map to?

R99 maps to 134 SNOMED CT concepts: 7878000, 65819004, 74660000, 44633000, 242055009, and 129 more. SNOMED CT is a clinical terminology used in electronic health records.

What are the UMLS CUIs for R99?

R99 is linked to 3 UMLS Concept Unique Identifiers: C0277589, C0478195, C1408354. The UMLS (Unified Medical Language System) integrates multiple biomedical vocabularies maintained by the U.S. National Library of Medicine.

How does R99 relate to ICF functioning codes?

ICF (International Classification of Functioning, Disability and Health) codes describe how conditions like ill-defined and unknown cause of mortality affect a person's functioning — body functions, activities, participation, and environmental factors. AutoICD provides ICF Core Sets for 12+ conditions and can map clinical text to ICF categories automatically. Browse the ICF directory to explore functioning codes.

What is the ICD-11 equivalent of R99?

R99 maps to the ICD-11 code: MH14 (Other ill-defined or unspecified causes of mortality).

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Includes SNOMED Clinical Terms® (SNOMED CT®) used by permission of SNOMED International. Includes content from the UMLS Metathesaurus, courtesy of the U.S. National Library of Medicine.