A swollen ankle, on its own, does not identify which organ is responsible. The same sign may accompany prolonged immobility, a venous problem, medication or heart or kidney disease. So the right question is not just ‘which of the two?’, but also: how long has it been happening, is it on one side or both, and what other symptoms are present?
First, distinguish what can wait from what cannot
Sudden, significant or painful swelling, especially in just one leg, warrants prompt medical advice. Redness or warmth in the area is also a sign that should be assessed. This does not prove that there is a blood clot, but it is not simply a case of heavy legs after a day spent standing either.
If the swelling is accompanied by difficulty breathing, chest pain or feeling faint, call the emergency services: 112 in Luxembourg and across the European Union. Do not start by comparing your ankles with photographs on the Internet. This combination of symptoms could indicate an emergency.
The UK NHS clearly distinguishes persistent swelling that should be assessed from symptoms requiring urgent care. Its emergency numbers are for the UK; for readers in Luxembourg, call 112 in an emergency.
Evening offers a clue, not an answer
The word oedema describes a build-up of fluid in the tissues. It describes a phenomenon, not a diagnosis. Remaining seated or standing for a long time, an injury, certain medicines and various illnesses are among the possible causes listed by the NHS.
This range of causes explains why the time when you notice the swelling is not enough to identify it. Evening is also when people take off their shoes and look at their legs. An observation made at that moment does not tell you exactly when the problem began.
Likewise, having both ankles swollen does not mean you can conclude that the heart is responsible. Conversely, the absence of pain is not proof that everything is harmless. For a doctor, the location and progression of the swelling make sense in the context of a patient’s medical history, treatment and examination.
When the heart comes into the picture
The French health insurance system, Assurance maladie, describes four symptoms that should attract attention when they appear or occur together: breathlessness, unusual tiredness, oedema and rapid weight gain. In particular, an unexplained increase of two to three kilos over a few days may indicate a build-up of fluid.
Breathing difficulties change how the symptoms should be interpreted. Becoming more breathless during an activity that was previously well tolerated, or struggling to breathe when lying down, warrants assessment. This is still different from receiving a diagnosis remotely.
In its information sheet on heart failure, Assurance maladie explains that the assessment combines a clinical examination with appropriate investigations. Blood markers BNP or NT-proBNP can help guide the diagnosis. A heart ultrasound examines, among other things, the structure and function of the heart. These are elements of an assessment, not tests to interpret on their own at home.
What the kidneys may explain
The kidneys filter the blood. In nephrotic syndrome, their filters allow too much protein to pass into the urine. The condition is associated with, among other things, protein loss in the urine, low levels of albumin in the blood and oedema.
The NIDDK, a US institute whose work includes kidney disease, lists swollen eyelids, swollen legs or ankles, foamy urine and weight gain caused by retained fluid among the possible symptoms. Urine and blood tests can be used to look for these abnormalities.
The reasoning should not be reversed: foamy urine or a swollen eyelid is not enough to identify this syndrome. Nor does nephrotic syndrome account for all kidney diseases. The documented mechanism helps explain one possibility; it does not provide a self-diagnosis checklist.
Preparing for a useful consultation
Rather than choosing between two organs yourself, you can gather some simple information: when the swelling began, which side is affected, how it is progressing, whether there is any pain or breathlessness, and what medicines you take. If a change in weight has been noticed, how long it has lasted matters as much as the figure.
It is useful to explain what has changed in everyday life. ‘I now have to stop for a rest when I climb these stairs’ describes a change better than a simple ‘I’m tired’. This kind of observation helps you explain the problem without assigning it a cause.
Any recently started treatment should be mentioned, but not stopped on your own initiative. The purpose of the consultation is precisely to distinguish between possible causes and adapt treatment. New, persistent or worsening swelling warrants this approach; a breathing or chest emergency calls for the emergency services, without waiting for the appointment.
