Hello, I'm Dr. Deb and will do my best to help you today.
I'm sorry for this concern for your Maltese.
If she is otherwise acting fine, then you may be able to treat her symptomatically for a few days and she will get past this. Most patients with acute diarrhea will respond quite well if the following protocol is followed:
1. Feed a bland diet of 1 part boiled chicken (or hamburg) to 4 parts 20-minute white rice. Feed only a small amount of one time, 3-4 times through the day. I would not feed any regular dog food.
2. If she is not currently taking any aspirin or nsaid products and is not vomiting, then you can give Regular Strength Pepto Bismol. The dose would be 1 teaspoon per 10 lbs of body weight 2-3 times a day. For example, if she weighs 10-15 lbs, then her dose would be 1 teaspoon.
Pepto bismol should not be given to vomiting dogs since it contains salicylates (the active ingredient in Aspirin) which can irritate the stomach.
It can also turn the stools a greenish or grey color.
3. I'd start her on a good quality, canine probiotic such as Forti Flora or Resources Protegrity GI. These products can be extremely useful for gastrointestinal issues (and to help strengthen the immune system as well). They may be available at local pet/grain stores or can be purchased online.
If her stools continue to be loose for more than a few more days and/or she becomes lethargic and/or has no interest in eating or possibly starts to vomit, then a vet visit may be prudent.
I hope this helps and that you see improvement soon. Deb