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.)

Dear Doctor: I was recently diagnosed with giant cell arteritis, but I don't know what it is or how to treat it. My pain is above my right eye, and it gets worse when I'm eating.

Dear Reader: Giant cell (temporal) arteritis is an inflammatory condition of the body's large and medium arteries. Headaches such as yours are one of the most common symptoms. Some patients also experience jaw pain when eating, but more severe symptoms are also possible. We'll explore that later.

First, let's focus on the basics of giant cell arteritis (GCA), a condition whose cause is largely unknown. GCA is more likely to develop after the age of 50 and occurs more frequently in people of Northern European ancestry; it is exceedingly rare in people of African, Asian or Latin descent. Atherosclerosis and a history of smoking increase the risk in women, but not in men. GCA is also associated with an inflammatory muscle condition, polymyalgia rheumatica; in fact, GCA occurs in about 15 percent of patients with polymyalgia rheumatica. If GCA is caused by infection, no link has yet been found.

What is known about GCA is that the immune system attacks and inflames the blood vessel walls, especially those within the head. Aside from causing headaches and jaw pain when eating, this inflammation can lead to fever, decreased appetite and weight loss. When GCA affects the medium-sized arteries going to the eye, it can lead to a temporary loss of vision in one or both eyes, but the most feared common symptom of GCA is permanent vision loss. Partial or complete vision loss in one or both eyes occurs in 15 to 20 percent of people with GCA. Sometimes these symptoms occur suddenly. A daily baby aspirin appears to lower the risk.

GCA can also attack the large vessels of the body, including the aorta and the arteries that go to the limbs. Involvement of the aorta can lead to aneurysms within the artery and a risk or rupture of the large blood vessel. In GCA, the aorta in the chest is more likely to be involved than the aorta in the abdomen. That means people with the condition -- including you -- should be screened for aneurysms of the aorta. When the arteries to the limbs are affected, people can experience sensations of cold in their feet and hands.

Diagnosis begins with a recognition of symptoms consistent with GCA, and then the discovery of an elevated blood sedimentation rate and/or an elevated C-reactive protein level. A temporal artery biopsy is necessary for complete confirmation.

Due to the worries regarding blindness, GCA should be treated quickly with high doses of anti-inflammatory steroids, usually the oral medication prednisone. However, if vision loss is apparent, high-dose intravenous methylprednisolone is needed before the prednisone. In both cases, the prednisone must be gradually lowered over a nine- to 12-month period due to the possible side effects of chronic steroid use, including diabetes, osteoporosis, weight gain and an increased risk of infection. Because of the possibility of side effects, some people have used the arthritis drugs tocilizumab or methotrexate in addition to a shorter course of prednisone.

In summary, immediate treatment with high-dose steroids is the first and most important step, as is an evaluation of your aorta for potential aneurysms. A diagnosis of giant cell arteritis means you have to be proactive about your own health. Asking questions is the first step.

(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.)