Possible Clues:

• Indicating the nature of an illness
• A distinctive problem in upsetting papers by religious sceptic
• Identifying problem in clubs — it's about key support coming back
• Support return of knowledge of problem solving
• Specific symptom
• Distinctive symptom or characteristic (of a disease)
• Analytical
• A symptom used to identify a disease
• Help rejected by old heretic? That's symptomatic!
• Working out problem, I had backtracked, lacking certainty