Although personality disorders are very common in middle aged people, they are not that often diagnosed in a nursery home. This is probably so because a doctor will more likely look at a kidney malfunction than at someone his personality. However, there is one sort of personality disorder that is not likely to miss and that one is the Borderline Personality disorder.
You can easily recognize someone with Borderline personality disorder as these persons are very good in claiming your attention on a passive aggressive way. They know very well how to manipulate you and others and in that way get as much attention as needed. Dealing with these disorders is very hard as a person with borderline is not able to empathize feelings of others.
The best way in dealing with borderline personality disorder is by giving a lot of structure to the person. Always tell what the rules are and that everybody should stick with the rules. A borderlines will try to find the edge and it is best to clearly state those borders.