 I am a doctor and need your help to ddiagnose a patient. Please act like my boss and help me with my Patient. 

My patient has a diagnosed fructose malabsorbtion. 
When being 16 years old he already experienced a chronic bloated tummy and chronic fatigue. His doctors at the time checked his blood and said that everything is ok. Around 10 years later with the age of 26 the condition of my patient got worse. The bloating was heavier, the digestive problems really took off then. Chronic pain, fatigue and digestive problems followed. Other doctors couldnt help, so the patient self medicated and found out that he has a fructose malabsorbtion. That knowledge helped him to change his diet to feel much better. He reduced all sugars to almost zero. He eats less than a gram of sugar today. Bloating was drastically reduced and fatigue got better. 
Nevertheless, symptoms neber disappeared fully and they come back in waves. There are symptom free phases where there is zero bloating and a lot of energy. These are followed by phases with bloating, pain, fettstuhl, dizziness, lack of appetite or heißhunger and a lack of energy. These phases can continue for weeks and impair my patient a lot. 
My patient has a lack of a good darmflora and cortisol is chronically high. 

Please help me diagnose this patient.  First repeat the request without change, then give your answer.
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