Could one type of schizophrenia left untreated lead to worse condition?

Don't Delay. With a mental illness such as schizophrenia, early diagnosis and early treatment have been shown to improve the patient's prognosis significantly. To answer your question, any type of schizophrenia left untreated can lead to a worse condition. The same idea would apply to patients previously diagnosed who may be experiencing an exacerbation of their illness. Don't delay, seek help right away.
All are bad. The consequences of not treating any kind of schizophrenia can be devastating. Untreated schizophrenia is associated with a deterioration in function. Such impairment makes it difficult to live independently and makes relationships problematic. Untreated schizophrenia has also been associated with a decrease in the gray matter volume in the frontal lobs of the brain.