AIDS, cancer, cardiac, diabetic, heart, etc.
surgical, transplant
developments that will help surgical patients recover more quickly

mental, psychiatric
depressed, mentally ill
seriously ill, severely ill, terminally ill
high-risk (esp. AmE), vulnerable (esp. BrE)
hospital
private (esp. BrE)
He only takes private patients.

elderly, older
adult, child
paediatric/pediatric

assess, examine, see, treat
She sees an average of 35 patients every day.

admit
The patient was admitted to hospital yesterday.

discharge
patients waiting to be discharged from hospital

refer (to sb/sth), transfer (to sth)

develop sth, have sth, suffer from sth
The patient has a severe heart condition.

suffer sth
patients who have suffered a heart attack

be diagnosed with sth
The patient was first diagnosed with malaria.

present with sth
Many patients present with conditions that cannot be easily diagnosed.

respond (to sth)
These patients are responding well to the new drug.

improve
receive sth, undergo sth
Patients undergoing chemotherapy may be at a higher risk of infection.

care

patient with
patients with liver disease

be, sound
remain

extremely, fairly, very, etc.
incredibly
endlessly (esp. BrE), infinitely

about
She's been extremely patient about it all.

with
He was endlessly patient with the children.