Experienced doctors often glance at a patient's hands early in a physical exam, and there is a good reason for it.
Several systemic conditions leave visible traces on the palms, fingertips and knuckles before they cause more obvious symptoms elsewhere in the body.
Most of the classic clues fall into five groups. Persistently red palms can point to the liver.
Rounded, bulging fingertips may signal chronic lung or heart trouble. Fingers that turn white or blue in the cold suggest a circulation problem, sometimes tied to an autoimmune disease.
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Swollen, tender knuckles that feel stiff in the morning are a hallmark of rheumatoid arthritis. And a faint shake in one hand at rest is one of the earliest recognized signs of Parkinson's disease.
None of these is a diagnosis on its own. Each is a reason to look closer, and to ask a doctor to do the same.
Red palms and the liver
Palmar erythema is a blanchable, reddish flush of the palms, most obvious on the fleshy pad below the little finger.
According to a review of skin changes in cirrhosis published in the NIH's PubMed Central library, almost 23 percent of people with liver cirrhosis develop palmar erythema, and the redness is thought to result from abnormal estrogen levels driving dilation of small blood vessels in the skin.
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The same color change can appear in pregnancy, thyroid overactivity and rheumatoid arthritis, and sometimes in healthy people.
Red palms that persist without a clear explanation, especially alongside fatigue, easy bruising or a yellow tint to the skin or eyes, are worth flagging to a physician.
Clubbed fingertips and the lungs or heart
Finger clubbing is a slow rounding and bulging of the fingertips, with the nails curving downward like an upside-down spoon. The NIH's MedlinePlus encyclopedia lists lung cancer as the most common cause, along with chronic lung infections, interstitial lung disease, congenital heart defects and infection of the heart valves.
The mechanism is not fully understood, but clubbing typically reflects long-standing low blood oxygen. MedlinePlus advises anyone who notices clubbing to contact a health care provider, because the underlying cause needs to be identified.
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White or blue fingers in the cold
Fingertips that suddenly turn white, then blue, then flush red when the hands warm up are the signature of Raynaud's phenomenon. The National Institute of Arthritis and Musculoskeletal and Skin Diseases describes attacks in which blood vessels in the hands and feet narrow quickly in response to cold or stress, cutting off flow until the fingers pale, then take on a bluish, numb, cold appearance before turning red as circulation returns.
Primary Raynaud's has no known underlying cause and tends to be mild. The secondary form is linked to other conditions, especially autoimmune diseases such as lupus, scleroderma, rheumatoid arthritis and Sjögren's disease, and is more serious. Attacks that leave sores on the fingertips, or that first appear after age 40, deserve medical evaluation.
Swollen, stiff morning knuckles
Rheumatoid arthritis often announces itself in the hands. The NIAMS overview of the disease describes joint pain, tenderness, warmth and swelling that typically strike the same joints on both sides of the body, along with morning stiffness that lasts more than 30 minutes after waking or after long rest.
NIAMS notes that rheumatoid arthritis is most common in the wrists, hands and feet. Because untreated disease can damage joints permanently, the institute urges early evaluation when persistent symmetric joint symptoms appear.
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A quiet tremor at rest
A faint shaking in a finger, thumb or hand that shows up when the limb is completely relaxed is listed by the Parkinson's Foundation as the first of ten early signs of Parkinson's disease. A resting tremor stands out because it fades when the person actually uses the hand.
Shaking after heavy exercise, during acute stress, after an injury or as a medication side effect is common and usually not a Parkinson's clue. Because tremor is only one of the early warning signs of Parkinson's disease, the Foundation advises that anyone noticing more than one of them should book an appointment with a doctor.
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This article is made and published by Jesper Bengtson, who may have used AI in the preparation.