White lesions are the most impressive, but “inflammatory thrush” is only red. Note the reddish components in these pictures, then imagine that you see them in a mouth without any white plaque
Note that Thrush is rarely (never?) just on the tongue.
2. Hairy Leukoplakia
Vertical corrugated white streaks on the sides of the tongue. These pictures show extensive manifestations, but try to imagine a patient with only a fraction of what’s shown here.
Hairy leukoplakia can look just like white streaks due to occlusal trauma from sharp molars that scratch the tongue. I may have a patient stick their tongue in and out a few times while I squint to see where a wayward tooth-edge might contact.
3. Kaposi’s Sarcoma
Ecchymoses on the palate (may or may not be palpable):
Suspect HIV if severe gingivitis over and above simple lack of hygiene.