Appeal type: Medical necessity
Decision: Upheld

Diagnosis: Respiratory System. 
Treatment: Advanced imaging services. 
The health plan denied computed tomography (CT) of the chest without contrast. 
The denial is upheld.

The patient is a female being cared for by an infectious disease provider. She was referred after being diagnosed by her pulmonologist with mycobacterium avium intracellulare infection (MAI) non-tuberculosis mycobacterial (NTM) after a bronchoscopy. She was also being treated for hypertension (HTN), hyperlipidemia (HLD), and depression. The provided records do not include any pathology or microbiology reports so it cannot be confirmed how non-tuberculous mycobacterial infection (NTM) was diagnosed. Records state she was treated with Azithromycin/Rifampin/Ethambutol for 18 months. She had follow-up chest computed tomography (CT) scans every 6 months. She was seen after a follow-up chest CT done showed no new areas of infection and slight improvement in the other areas. Note states she was complaining of occasional night sweats and visual disturbances. She was advised to continue on treatment and return in 6 months. She returned to review follow-up chest CT done, which was stated as unchanged from the previous scan. Her treatment was then continued for another 6 months. A repeat chest CT was stated to show "some improvement but did note scattered areas of bronchiectasis and a very similar appearance of disease." Treatment was discontinued on her follow-up visit and she was advised to follow-up with her pulmonologist. Exam at that visit noted a completely normal lung exam, and in the assessment plan stated MAI treatment completed, no further treatment needed.  The subject under review is the medical necessity for a CT of the chest without contrast.

The health plan's determination is upheld.

The requested CT of the chest without contrast is not medically necessary.  Per the most current Infectious Diseases Society of America (IDSA) guidelines, the diagnostic criteria for NTM includes clinical, radiologic and microbiologic evidence of disease. Clinical findings include pulmonary and/or systemic symptoms, radiologic criteria include nodular or cavitary opacities on chest x-ray (CXR) or high resolution CT that shows bronchiectasis with multiple small nodules; microbiologic criteria include positive culture results from at least two separate expectorated sputum samples, or positive culture results from at least one bronchial wash or lavage, or transbronchial or other lung biopsy with mycobacterial histologic features (granulomata or acid fast bacillus [AFB]) and positive culture for NTM or biopsy showing mycobacterial histologic features and one or more sputum or bronchial washing that are culture positive for NTM.
Treatment regimens are determined by species of NTM and susceptibility testing.
Monitoring response to therapy: clinical, radiographic, and microbiologic data should be collected to determine response to therapy. Chest x-rays and chest CT "may be beneficial for defining a radiographic response to therapy, although there can be wide variability in findings given the common occurrence of underlying lung disease." Because duration of therapy is based on the time of culture conversion, frequent sputum collection is necessary. The recommendation is to obtain sputum cultures every 1-2 months in order to document when sputums become negative. In addition, clinical and radiographic response to therapy should be used to determine if patient is responding to treatment.
The need for repeat chest imaging in this patient, based on the records provided, is not medically necessary. There is no indication that this patient was symptomatic, and her lung exam was normal.