A raised IgE increases suspicion, though there is no universally accepted cut-off value. Values can be stated in international units (IU/mL) or ng/mL, where 1 IU is equal to 2.4 ng/mL. Since studies began documenting IgE levels in ABPA during the 1970s, various cut-offs between 833 and 1000 IU/mL have been employed to both exclude ABPA and to warrant further serological testing. The current consensus is that a cut-off of 1000 IU/mL should be employed, as lower values are encountered in SAFS and asthmatic sensitization.IgG antibody precipitin testing from serum is useful, as positive results are found in between 69 and 90% of patients, though also in 10% of asthmatics with and without SAFS. Therefore, it must be used in conjunction with other tests. Various forms exist, including enzyme-linked immunosorbent assay (ELISA) and fluorescent enzyme immunoassay (FEIA). Both are more sensitive than conventional counterimmunoelectrophoresis. IgG may not be entirely specific for ABPA, as high levels are also found in chronic pulmonary aspergillosis (CPA) alongside more severe radiological findings.Until recently, peripheral eosinophilia (high eosinophil counts) was considered partly indicative of ABPA. More recent studies show that only 40% of people with ABPA  present with eosinophilia, and hence a low eosinophil count does not necessarily exclude ABPA; for example patients undergoing steroid therapy have lower eosinophil counts. Radiological investigation
Consolidation and mucoid impaction are the most commonly described radiological features described in ABPA literature, though much of the evidence for consolidation comes from before the development of computed tomography (CT) scans.
Both of these contraindications are controversial 
Poorly controlled psychosis
Severe liver disease such as cirrhosis
Pregnancy
Active substance use disorder (for serial ketamine injections)
Age less than 3 months

Side effects
At anesthetic doses, 10–20% of adults (1–2% of children) experience adverse psychiatric reactions that occur during emergence from anesthesia, ranging from dreams and dysphoria to hallucinations and emergence delirium. Psychotomimetic effects decrease adding lamotrigine and nimodipine and can be counteracted by pretreatment with a benzodiazepine or propofol. Ketamine anesthesia commonly causes tonic-clonic movements (greater than 10% of people) and rarely hypertonia. Vomiting can be expected in 5–15% of the patients; pretreatment with propofol mitigates it as well. Laryngospasm occurs only rarely with ketamine. Ketamine, generally, stimulates breathing; however, in the first 2–3 minutes of a high-dose rapid intravenous injection it may cause a transient respiratory depression.At lower sub-anesthetic doses, psychiatric side effects are prominent. Most people feel strange, spacey, woozy, or a sense of floating, or have visual distortions or numbness. Also very frequent (20–50%) are difficulty speaking, confusion, euphoria, drowsiness, and difficulty concentrating. The symptoms of psychosis such as going into a hole, disappearing, feeling as if melting, experiencing colors, and hallucinations are described by 6–10% of people. Dizziness, blurred vision, dry mouth, hypertension, nausea, increased or decreased body temperature, or feeling flushed are the common (>10%) non-psychiatric side effects. All these adverse effects are most pronounced by the end of the injection, dramatically reduced 40 minutes afterward, and completely disappear within 4 hours after the injection.