Coronavirus?

Information comes fast and furious on SARS. Here is the latest – New Coronavirus Suspected as Cause of Severe Acute Respiratory Syndrome

During a telebriefing Monday, the director of the US Centers for Disease Control and Prevention, Dr. Julie Gerberding, reported that the agency now has “very strong evidence supporting coronavirus in the etiology of severe acute respiratory syndrome or SARS.”

It may be a “new or emerging coronavirus,” she said.

According to Dr. Gerberding, the CDC has been able to culture coronavirus in tissue from two of four affected patients. “That, in and of itself self does not prove causality,” Dr. Gerberding said, “but what is interesting to us is that not only are we culturing it but we are finding it in affected tissues.” In one patient, the virus was found in lung tissue and secretions as well as the kidney, she said.
Moreover, Dr. Gerberding said the patient had a negative early antibody test for coronavirus, but by the end of the illness had seroconverted “using a very specific assay for this new coronavirus.”

She said CDC also has evidence of coronavirus infection in seven other people. “A total of three have seroconverted and we are actively getting late serum to see if others will seroconvert as their illness progresses.”

“We know from sequencing pieces of the virus DNA that it is not identical to the coronaviruses that we have seen in the past. This may very well be a new or emerging coronavirus infection, but it is very premature to assign a cause,” Dr. Gerberding told reporters.

So what is coronavirus? I found this link that gives some information – Human coronavirus. It appears to be a cause of the common cold. At this time we must suspect a mutation has allowed this virus to cause pneumonia. As regular readers know, we will follow this story closely as it unfolds.

Chronic cough and GERD

Patients often present to their generalist complaining of a common cough. We teach residents to consider a complete differential, but to concentrate on the four most common diagnoses – undiagnosed asthma, ACE inhibitor cough, post-nasal drainage, and gastroesophageal reflux disease (GERD). This month’s CHEST has a very interesting article on the later diagnosis. This link probably will only work if your library has a subscription to CHEST online – Chronic Cough and Gastroesophageal Reflux Disease* Experience With Specific Therapy for Diagnosis and Treatment

One hundred eighty-three patients were identified with chronic cough and were included in the study. Thirty-one patients were disqualified because of abnormal chest radiographic findings, inadequate follow-up, or cough being not the primary complaint. Fifty-six patients were identified as having GERD-related cough.

This simple paragraph suggests that approximately 30% of chronic cough patients have their cough related to GERD. This is important information. They then ask the important question – does treatment matter?

GERD was the single cause of cough in 24 patients (43%). Twenty-nine patients (52%) had GERD plus another cause, and 3 patients (5%) had GERD with more than two causes. Twenty-four patients (43%) had cough only, while 32 patients (57%) had other symptoms of GERD. Proton-pump therapy was successful in 42 patients (79%). Twenty-four patients responded to proton-pump inhibitor therapy, and 18 patients responded when metoclopramide or cisapride was added. The remaining two patients responded to a histamine type-2 blocker or cisapride alone. The cough was eliminated or markedly improved in 38 patients (86%) after 4 weeks and by 8 weeks in the remaining 6 patients. Six of the nonresponders had aspiration diagnosed by bronchoscopy. Four patients had fundoplication recommended, and two patients responded to alternative interventions.

Many patients need a ‘prokinetic agent’ in addition to the PPI. We no longer have the option of using cisapride, thus we will generally try metoclopramide (Reglan). This study helps place GERD into perspective as a chronic cough etiology. An accompanying editorial (by a fellow UAB faculty member) places this into clinical context.

Also, who should be considered for an empiric trial? Obviously, patients with esophageal symptoms should be considered. However, a large number of patients have clinically “silent” GER. Irwin and Madison6 have described the clinical profile of a patient with cough due to silent GER, as someone who is a nonsmoker, is not receiving an angiotensin-converting enzyme inhibitor, has not been exposed to environmental irritants, who has a normal or near-normal chest radiograph finding showing nothing more than stable inconsequential scarring, and in whom asthma, rhinosinus diseases, and eosinophilic bronchitis have been ruled out or have been adequately treated.6 These patients also should be considered for an empiric trial.

Her excellent editorial – Chronic Cough Practical Considerations

Doctors treat injured of both sides

Being a physician is a constant source of pride. When I look in the mirror each morning, I know that my goals are to improve people’s lives. Navy Docs can believe the same thing. ‘Devil Docs’ operate on friend and foe: In field operating room, wounds matter more than sides . This is as it should be!!

The most badly wounded fighters from the front lines are treated first, regardless of whether they are friend or foe.

“It’s a medical decision based on the patient’s physiology and the wound,” said Capt. John Percibelli, the chief surgeon. “That’s how we decide who goes first.”

Insulin resistance revisited

I often rant about exercise and diet. The information in this link is not new – even to this blog. However, it is important enough to highlight once again. Eat less and walk more to keep diabetes at bay.

Problems with insulin resistance are not confined to obesity and have much wider metabolic implications ? hence the other term for the condition, the metabolic syndrome. As well as a resistance of the body tissues to insulin, the patient may have high levels of circulating blood insulin, obesity, high blood pressure, abnormal blood fat levels ? the combination of high blood pressure and raised triglyceride blood fats is a particularly ominous one ? and type 2 diabetes. In women, there is also an association between insulinresistance syndrome and polycystic ovarian syndrome. In the present epidemic of childhood and adolescent obesity, it is found that however the fat is distributed, an overwhelming number of patients are insulin-resistant and potential candidates for type 2 diabetes.

There is a strong familial and racial pattern to insulin- resistance syndrome. It is common in Asia, but in all countries of the world it is increasing. One way of countering it and the ever-increasing numbers of patients suffering from type 2 diabetes that stems from it is to reduce the prevalence of obesity. This may be achieved by reducing the calorie intake, and by increasing exercise. The change doesn?t have to be dramatic; by cutting the calorie intake by 600 a day, and by walking briskly for an extra half mile a day, a dramatic difference may be observed after a year.

Professor Thomas Wadden, from the US, had an interesting observation on the obesity associated with insulin-resistance syndrome. He has found that many of these patients are binge-eaters. Between 15 and 20 per cent of the obese patients who attend his clinic fall into this category. Many of the binge-eaters he treats are also depressed and have a typical depressed patient?s diurnal variation ? that is to say they become progressively more jolly as the day wears on. This has an effect on their eating pattern. Although they are hearty eaters at supper time and night-raiders of the fridge, they are anorexic at breakfast and have a very light lunch.

As I rant incessantly – diet and exercise – exercise and diet.

The latest on SARS

Singapore and Vietnam are home to a third wave of SARS cases. Fortunately, investigators can still link these cases directly to previous cases (in terms of exposure). As evidence accumulates, one must have close contact to an infected individual. Barrier precautions do apparently work. Respiratory Illness Spreads to a Third Wave of Cases.

Scientists at the University of Hong Kong, a member of the W.H.O.’s collaborative network, have isolated a virus in recent days that is a prime suspect. Yesterday, the agency reported further progress in identifying the virus and developing a test for it.

Scientists seeking to identify the virus are taking the utmost precautions as they work in highly secure laboratories categorized at the “three-plus” level, half a step below the maximum-security level-four labs. They wear masks and gowns, all materials in the room are burned after use, and the room is steam cleaned before it is used again.

Dr. Klaus St�hr, who is leading the W.H.O. scientific team investigating the illness, said members of the agency’s laboratory network would not distribute the suspect virus to any laboratory without three-plus level capability until it was determined that it was safe to do so.

The illness “still looks like a disease you get only after close contact with an ill person,” said Dr. Heymann, executive director in charge of communicable diseases for the W.H.O. The new information, he said, “shows a typical epidemic curve of successive waves of transmission of a disease that is transmitted person to person,” referring to graphs that epidemiologists construct to plot the progress of outbreaks.

It appears that approximately 10 per cent of cases become very severe.

The W.H.O. has established a network of doctors who have cared for at least one patient with the illness. After speaking with each other in teleconferences, their initial impression is that about 10 percent of the cases become so-called rapid progressors because the condition of the patients declined so quickly, Dr. Heymann said.

About half of the rapid progressors ? 5 percent of total cases ? develop such severe difficulty in breathing that they have to be connected to mechanical respirators. Most deaths have occurred among those who needed mechanical respiratory support. Even among the other patients, many experience breathing trouble, one reason that an overwhelming majority remain in hospitals.

We can only hope that precautions will allow containment of this infection. However, we are already in the 3rd wave and this could get worse. We must follow this story carefully and be ready in case this infection becomes endemic. As an aid to keeping up to date, here is the CDC web page with the latest information – CDC – Severe Acute Respiratory Syndrome.