Dear Doctor: My husband, who has been diagnosed with a sleep disorder, acts out all his dreams. He recently tore his rotator cuff and dislocated his shoulder when he fell out of bed during a dream about playing basketball. We're worried this might happen again. Are there any new treatments or research into this disorder?

Dear Reader: It sounds as though you're describing what's known as REM Sleep Behavior Disorder. This happens when an individual overcomes the natural paralysis that typically accompanies the dream state and literally engages in the physical activities of the dream.

We spend our time in two basic stages when we sleep. There's REM (rapid eye movement) sleep, which is when we dream. And there's non-REM sleep, which is made up of several different stages of deeper sleep. Throughout the night, we cycle through these different stages, with up to a quarter of the time spent in REM sleep, and the rest in the various stages of non-REM sleep.

During REM sleep, blood pressure goes up, breathing becomes uneven, the eyes dart back and forth, and the brain is extremely active. In normal REM sleep, a natural paralysis sets in, which ensures that our dreams remain in our minds and don't cross into the physical realm. However, in REM Sleep Behavior Disorder, also known as RBD, that paralysis is either incomplete or not present at all. As a result, the sleeper takes an active part in those dreams.

The behaviors of RBD range from speaking, shouting and swearing in one's sleep, to running, leaping, grabbing and punching. Patients report that their dreams are always active, and often violent. Although this time it was your husband who was hurt, those who share a bed with someone with RBD are also at risk of physical injury.

At this time, treatment consists of making the bedroom safer for the patient and his or her bed partner, and medications for the patient. Padding on, around and below the bed, lowering the bed itself, and de-cluttering and removing potentially dangerous objects, is recommended. When it comes to medications, the anti-anxiety drug klonopin has been shown to be effective. Sometimes melatonin, a regulator of the sleep cycle, is prescribed as well.

Although the cause of REM Sleep Behavior Disorder is not yet known, studies have found a link between the disorder and the future onset of degenerative neurological conditions like Parkinson's disease. According to the authors of the most recent study, published in the journal Neurology Today in September 2017, up to 75 percent of patients eventually develop Parkinson's or a related condition. The thinking is that the symptoms of RBD indicate neurological changes that precede the symptoms of Parkinson's and other similar disorders.

We realize this sounds alarming, which is why we urge you and your husband to get a second opinion at a recognized sleep center. Your husband will undergo a physical and neurological exam, may be asked to undergo an overnight sleep study, and you may be interviewed for details about his sleep patterns. If the RBD diagnosis proves accurate, you will then be in good hands to deal with the disorder.

(Send your questions to askthedoctors@mednet.ucla.edu, or write: Ask the Doctors, c/o Media Relations, UCLA Health, 924 Westwood Blvd., Suite 350, Los Angeles, CA, 90095. Owing to the volume of mail, personal replies cannot be provided.)

Dear Doctor: It was really scary to read about the man who lost parts of his hands and feet after a bout of strep throat. What's going on? I get strep fairly often; am I at risk too?

Dear Reader: Considering that strep throat is a common infection that typically results in a sore throat, the news reports you're referring to were indeed alarming. We suspect you have quite a few fellow strep sufferers also wondering whether that next episode will turn out to be deadly.

Let's start with reassuring news. For a strep infection to move beyond the throat and tonsils and wreak the kind of havoc we heard about in that case is extremely rare. That's why stories like those get such prominent play in the news. To put things into perspective, just 3.5 of every 100,000 cases of strep will go on to cause severe complications, according to the Centers for Disease Control and Prevention.

Strep throat occurs when the throat or tonsils (or both) become infected with group A Streptococcus bacteria, often referred to simply as "group A strep." It's a lot more common in children, but as you know from experience, adults do get it as well. The bacterium, which is highly contagious, spreads through contact with the spray of tiny droplets from an infected person's sneeze or cough, or with the skin rash that can sometimes appear. Transfer those droplets to your own nose, mouth or eyes, and you're at risk of becoming infected.

Symptoms often begin with a painful sore throat, which develops quite rapidly. A case of strep throat often includes fever, headache, swollen lymph nodes and distinctive white spots that appear on the roof of the mouth, tonsils, and soft and hard palate. You can have many of these symptoms but not have strep. You can also be exposed to strep and not become visibly ill. And while certain symptoms can suggest a strep diagnosis, a throat swab is the only way to definitively diagnose the infection.

In the case you mentioned, a 44-year-old man whose son had recently recovered from strep throat became ill with flulike symptoms. He tested negative for strep. He soon developed severe abdominal pain, which was accompanied by visible swelling. This led to exploratory surgery, which revealed a large quantity of infected pus within his abdomen. Typically, this is due to a puncture in an organ such as the colon, but none was found. It wasn't until a red rash appeared on the man's chest that his baffled medical team realized the patient had developed a strep infection in his abdomen.

Unfortunately, the infection had a head start and caused the man to go into septic shock. This inflammatory response to infection causes a life-threatening drop in blood pressure that can lead to organ failure, respiratory failure and stroke. The medical team was able to control his infection, although the treatment caused tissue death, which required partial amputation of his feet and fingers.

It's a difficult story with a challenging outcome, which is why we're going to repeat ourselves -- this type of complication from a strep infection is exceedingly rare.

(Send your questions to askthedoctors@mednet.ucla.edu, or write: Ask the Doctors, c/o Media Relations, UCLA Health, 924 Westwood Blvd., Suite 350, Los Angeles, CA, 90095. Owing to the volume of mail, personal replies cannot be provided.)

Dear Doctor: I thought the elderly were at the greatest risk of flu-related death, but I've seen more than a few headlines about children who have died. Who's more at risk?

Dear Reader: Flu season is here and even at this early stage, lives have been lost. According to the Centers for Disease Control and Prevention, several elderly patients and at least one child died from flu-related causes in October. As we'll discuss in a moment, it's not the flu itself that is so dangerous, but the complications that can arise.

The flu is a highly contagious respiratory illness caused by the influenza virus. It can infect the nose, throat and lungs, resulting in symptoms that range from mild to quite severe. Symptoms include fever, chills, sore throat, a persistent cough, congestion of the lungs and sinuses, headache, fatigue, muscle aches, and even diarrhea and vomiting. You also know that you can go from feeling just a little fluish to all-out sick in a short period of time.

While the flu can seem like nothing more than a nasty cold, the risk of grave complications is quite real. The majority of us will recover in a few days up to a week or two, depending on how hard we are hit. But for some individuals, the disease progresses in ways that can be life-threatening.

As you noted, older adults are at greater risk of both the flu as well as complications from the disease. After the age of 65, our immune systems are no longer as robust. The same is true of children. Those younger than 5, and particularly those younger than 2, are at risk of serious complications. They are not alone. Others at risk include pregnant women; individuals with certain medical conditions, like asthma, diabetes, chronic lung and heart disease; and anyone with a suppressed immune system due to chronic disease or immunosuppressive medical treatment.

For most of us, the flu means a few miserable, feverish, coughing, sneezing and achy days in bed as our immune systems rally and fight off the virus. For those at high risk, though, a range of complications is possible. These include bronchitis, sinus infections, ear infections and pneumonia. Even more grave is the chance of developing myocarditis, an inflammation of the heart, and encephalitis, an inflammation of the brain. In extreme cases, the body's inflammatory response to a flu infection can go into overdrive and lead to sepsis, which is a life-threatening condition requiring immediate treatment.

We encourage our patients to get an annual flu vaccine, available in the fall. According to the CDC, children who have received a flu vaccine lower their risk of hospitalization due to complications by 74 percent. In people 50 and older, that risk drops by 57 percent. Yes, the vaccine carries potential side effects that include soreness at the site of injection, headache, nausea and fever. But these are mild, not very common, and last just a day or two. When you compare these side effects to the discomfort, lost time and potential health risks of the flu, we think it's a fair trade-off.

(Send your questions to askthedoctors@mednet.ucla.edu, or write: Ask the Doctors, c/o Media Relations, UCLA Health, 924 Westwood Blvd., Suite 350, Los Angeles, CA, 90095. Owing to the volume of mail, personal replies cannot be provided.)