The most common is M. pneumonia (which causes walking pneumonia), but there are a number of other sp that can cause illness.
health.nytimes.com/health/guides/disease/atypical-mycobacterial-infection/overview.htmlSymptoms:
Fever
Weight loss
Enlarged lymph glands
Diarrhea
Sweating, excessive -- night sweats
Fatigue
General discomfort, uneasiness or ill feeling (malaise)
Cough
Shortness of breath (dyspnea)
Skin lesions
Joint pain
Bone pain
Additional symptoms that may be associated with this disease:
Paleness
Flank pain