ICD-10-CM Code G03.9

Meningitis, unspecified

Version 2020 Billable Code

Valid for Submission

G03.9 is a billable code used to specify a medical diagnosis of meningitis, unspecified. The code is valid for the year 2020 for the submission of HIPAA-covered transactions. The ICD-10-CM code G03.9 might also be used to specify conditions or terms like adhesive arachnoiditis, arachnoiditis, basilar meningitis, decreased flexion, hemorrhagic meningitis, idiopathic hypertrophic pachymeningitis, etc

Short Description:Meningitis, unspecified
Long Description:Meningitis, unspecified

Tabular List of Diseases and Injuries

The Tabular List of Diseases and Injuries is a list of ICD-10 codes, organized "head to toe" into chapters and sections with guidance for inclusions, exclusions, descriptions and more. The following references are applicable to the code G03.9:

Inclusion Terms

Inclusion Terms
These terms are the conditions for which that code is to be used. The terms may be synonyms of the code title, or, in the case of "other specified" codes, the terms are a list of the various conditions assigned to that code. The inclusion terms are not necessarily exhaustive. Additional terms found only in the Alphabetic Index may also be assigned to a code.
  • Arachnoiditis (spinal) NOS

Index to Diseases and Injuries

The Index to Diseases and Injuries is an alphabetical listing of medical terms, with each term mapped to one or more ICD-10 code(s). The following references for the code G03.9 are found in the index:


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

  • Adhesive arachnoiditis
  • Arachnoiditis
  • Basilar meningitis
  • Decreased flexion
  • Hemorrhagic meningitis
  • Idiopathic hypertrophic pachymeningitis
  • Leptomeningitis
  • Malignant meningitis
  • Meningitis
  • Meningitis following procedure
  • Metastatic malignant neoplasm of meninges
  • Neonatal meningitis
  • Non-infective meningitis
  • Nuchal rigidity
  • Nuchal rigidity due to meningitis
  • Pachymeningitis
  • Postoperative meningitis
  • Posttraumatic meningitis
  • Spinal arachnoiditis
  • Spinal effusion
  • Subdural effusion

Clinical Information

  • MENINGISM-. a condition characterized by neck stiffness headache and other symptoms suggestive of meningeal irritation but without actual inflammation of the meninges meningitis. spinal fluid pressure may be elevated but spinal fluid is normal. dejong the neurologic examination 4th ed p673
  • MENINGITIS-. inflammation of the coverings of the brain and/or spinal cord which consist of the pia mater; arachnoid; and dura mater. infections viral bacterial and fungal are the most common causes of this condition but subarachnoid hemorrhage hemorrhages subarachnoid chemical irritation chemical meningitis granulomatous conditions neoplastic conditions carcinomatous meningitis and other inflammatory conditions may produce this syndrome. from joynt clinical neurology 1994 ch24 p6
  • MENINGITIS ASEPTIC-. a syndrome characterized by headache neck stiffness low grade fever and csf lymphocytic pleocytosis in the absence of an acute bacterial pathogen. viral meningitis is the most frequent cause although mycoplasma infections; rickettsia infections; diagnostic or therapeutic procedures; neoplastic processes; septic perimeningeal foci; and other conditions may result in this syndrome. from adams et al. principles of neurology 6th ed p745
  • MENINGITIS HAEMOPHILUS-. infections of the nervous system caused by bacteria of the genus haemophilus and marked by prominent inflammation of the meninges. haemophilus influenzae type b is the most common causative organism. the condition primarily affects children under 6 years of age but may occur in adults.
  • MENINGITIS LISTERIA-. inflammation of the meninges caused by listeria monocytogenes infection usually occurring in individuals under the age of 3 years or over the age of 50 years. it may occur at any age in individuals with immunologic deficiency syndromes. clinical manifestations include fever altered mentation headache meningeal signs focal neurologic signs and seizures. from medicine 1998 sep;775:313 36
  • MENINGITIS MENINGOCOCCAL-. a fulminant infection of the meninges and subarachnoid fluid by the bacterium neisseria meningitidis producing diffuse inflammation and peri meningeal venous thromboses. clinical manifestations include fever nuchal rigidity seizures severe headache petechial rash stupor focal neurologic deficits hydrocephalus and coma. the organism is usually transmitted via nasopharyngeal secretions and is a leading cause of meningitis in children and young adults. organisms from neisseria meningitidis serogroups a b c y and w 135 have been reported to cause meningitis. from adams et al. principles of neurology 6th ed pp689 701; curr opin pediatr 1998 feb;101:13 8
  • MENINGITIS PNEUMOCOCCAL-. an acute purulent infection of the meninges and subarachnoid space caused by streptococcus pneumoniae most prevalent in children and adults over the age of 60. this illness may be associated with otitis media; mastoiditis; sinusitis; respiratory tract infections; sickle cell disease anemia sickle cell; skull fractures; and other disorders. clinical manifestations include fever; headache; neck stiffness; and somnolence followed by seizures; focal neurologic deficits notably deafness; and coma. from miller et al. merritt's textbook of neurology 9th ed p111
  • MENINGITIS VIRAL-. viral infections of the leptomeninges and subarachnoid space. togaviridae infections; flaviviridae infections; rubella; bunyaviridae infections; orbivirus infections; picornaviridae infections; orthomyxoviridae infections; rhabdoviridae infections; arenaviridae infections; herpesviridae infections; adenoviridae infections; jc virus infections; and retroviridae infections may cause this form of meningitis. clinical manifestations include fever headache neck pain vomiting photophobia and signs of meningeal irritation. from joynt clinical neurology 1996 ch26 pp1 3
  • TUBERCULOSIS MENINGEAL-. a form of bacterial meningitis caused by mycobacterium tuberculosis or rarely mycobacterium bovis. the organism seeds the meninges and forms microtuberculomas which subsequently rupture. the clinical course tends to be subacute with progressions occurring over a period of several days or longer. headache and meningeal irritation may be followed by seizures cranial neuropathies focal neurologic deficits somnolence and eventually coma. the illness may occur in immunocompetent individuals or as an opportunistic infection in the acquired immunodeficiency syndrome and other immunodeficiency syndromes. from adams et al. principles of neurology 6th ed pp717 9
  • MALARIA CEREBRAL-. a condition characterized by somnolence or coma in the presence of an acute infection with plasmodium falciparum and rarely other plasmodium species. initial clinical manifestations include headaches; seizures; and alterations of mentation followed by a rapid progression to coma. pathologic features include cerebral capillaries filled with parasitized erythrocytes and multiple small foci of cortical and subcortical necrosis. from adams et al. principles of neurology 6th ed p136
  • MENINGITIS CRYPTOCOCCAL-. meningeal inflammation produced by cryptococcus neoformans an encapsulated yeast that tends to infect individuals with acquired immunodeficiency syndrome and other immunocompromised states. the organism enters the body through the respiratory tract but symptomatic infections are usually limited to the lungs and nervous system. the organism may also produce parenchymal brain lesions torulomas. clinically the course is subacute and may feature headache; nausea; photophobia; focal neurologic deficits; seizures; cranial neuropathies; and hydrocephalus. from adams et al. principles of neurology 6th ed pp721 2
  • MENINGITIS BACTERIAL-. bacterial infections of the leptomeninges and subarachnoid space frequently involving the cerebral cortex cranial nerves cerebral blood vessels spinal cord and nerve roots.
  • MENINGITIS FUNGAL-. meningitis caused by fungal agents which may occur as opportunistic infections or arise in immunocompetent hosts.
  • MENINGITIS ESCHERICHIA COLI-. a form of gram negative meningitis that tends to occur in neonates in association with anatomical abnormalities which feature communication between the meninges and cutaneous structures or as opportunistic infections in association with immunologic deficiency syndromes. in premature neonates the clinical presentation may be limited to anorexia; vomiting; lethargy; or respiratory distress. full term infants may have as additional features fever; seizures; and bulging of the anterior fontanelle. from menkes textbook of child neurology 5th ed pp398 400
  • MENINGEAL CARCINOMATOSIS-. primary or secondary neoplasm in the arachnoid or subarachnoid space. it appears as a diffuse fibrotic thickening of the meninges associated with variable degrees of inflammation.

Convert G03.9 to ICD-9

Code Classification

  • Diseases of the nervous system (G00–G99)
    • Inflammatory diseases of the central nervous system (G00-G09)
      • Meningitis due to other and unspecified causes (G03)

Code History

  • FY 2016 - New Code, effective from 10/1/2015 through 9/30/2016
    (First year ICD-10-CM implemented into the HIPAA code set)
  • FY 2017 - No Change, effective from 10/1/2016 through 9/30/2017
  • FY 2018 - No Change, effective from 10/1/2017 through 9/30/2018
  • FY 2019 - No Change, effective from 10/1/2018 through 9/30/2019
  • FY 2020 - No Change, effective from 10/1/2019 through 9/30/2020

Information for Patients


Meningitis is inflammation of the thin tissue that surrounds the brain and spinal cord, called the meninges. There are several types of meningitis. The most common is viral meningitis. You get it when a virus enters the body through the nose or mouth and travels to the brain. Bacterial meningitis is rare, but can be deadly. It usually starts with bacteria that cause a cold-like infection. It can cause stroke, hearing loss, and brain damage. It can also harm other organs. Pneumococcal infections and meningococcal infections are the most common causes of bacterial meningitis.

Anyone can get meningitis, but it is more common in people with weak immune systems. Meningitis can get serious very quickly. You should get medical care right away if you have

  • A sudden high fever
  • A severe headache
  • A stiff neck
  • Nausea or vomiting

Early treatment can help prevent serious problems, including death. Tests to diagnose meningitis include blood tests, imaging tests, and a spinal tap to test cerebrospinal fluid. Antibiotics can treat bacterial meningitis. Antiviral medicines may help some types of viral meningitis. Other medicines can help treat symptoms.

There are vaccines to prevent some of the bacterial infections that cause meningitis.

NIH: National Institute of Neurological Disorders and Stroke

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