41 strange symptoms that can signal a serious disease

If your first thought is, well, we haven’t done that in a while, hang on: Bleeding after sex isn’t typical. There are a host of potential causes – ranging from vaginal dryness to cervical polyps – but cervical cancer also falls on that list. While it may be frightening, it’s important to bring it up with your GP who will consider a range of causes and work to rule out cervical cancer.

If you see a red rash in the shape of a bulls-eye popping up on your skin, you should immediately call your doctor. The first thing they’ll check for is Lyme disease. Caused by a tick bite, the disease can also cause more sneaky symptoms like fatigue, lack of focus and a sore throat. While only 70 to 80 percent of people develop a rash, it may also take on various shapes and colours, like multiple rashes or may even have a blue hue. If you notice these symptoms or anything out of the ordinary after spending time outside where Lyme-carrying ticks live, talk to your doctor.

Yep, this is really vague, but weird, vague “something isn’t right” symptoms should set off alarm bells – possibly for a heart attack. Women don’t always get the classic chest pain symptoms of a heart attack; it can manifest as more silent signs like feeling tired or upper back pain. “With anything out of the ordinary that suddenly pops up without a clear explanation, it doesn’t hurt to have a heart attack in the back of your mind,” says Dr. Sontag. Call your doctor or go to the ER. Head here to find out how to take control of your heart health.

With so many symptoms of celiac disease (300!), diagnosis can be difficult. And while GI issues like diarrhoea, constipation and bloating are common, so too are more head-scratching ones like mouth ulcers, reports Beyond Celiac. You may notice these in your cheeks, gums or lips and they can be painful. While it’s not a slam dunk for diagnosis, also watch out for other symptoms of celiac, like mood problems, joint pain and infertility.

If you’ve been hearing ringing or sounds are muffled in one ear, you may have an acoustic neuroma, a rare, non-cancerous and often slow-growing tumour, according to the Acoustic Neuroma Association. That’s not to say it’s not dangerous. As it grows, it can cause balance problems and even be life-threatening. If your doctor suspects this, an MRI can confirm the diagnosis. Find out more in this guide to keeping your hearing.

And you thought you just didn’t have to pluck them anymore. Hair loss, including from your eyebrows, can be a sign that your system is working sluggishly thanks to an underactive thyroid (also called hypothyroidism), says Dr. Sontag. Watch out for other symptoms like feeling cold all the time and constipation. Again, your doc will want to run a simple blood test to evaluate the function of your thyroid.

When you look down, suddenly you see a bunch of discolourations dotting your legs. Have you just been extra clumsy? Maybe, but it can also be leukaemia. Low blood platelet counts can make you more susceptible to bruises, notes the American Cancer Society. Of course, this doesn’t have to be your first worry, but if your doc suspects a problem, they will check your blood cell count before more invasive testing, like taking a bone marrow sample.

The primary place you likely suspect skin cancer is, well, your skin, but it can also appear on the skin of your nailbed, too. Called acral lentiginous melanoma (ALM), this type of skin cancer can look like a dark streak under your nail. If you don’t know what caused it (like smashing your finger in the door) and it’s recently appeared, see a dermatologist for an evaluation. Find out more about this alarming symptom here.

If your nose doesn’t perk up to various smells, your ears should perk up to the possibility of increased odds for Alzheimer’s disease, at least according to one new study published in Neurology. Three hundred people who already had a parent with the disease (and thus were considered higher risk) were asked to take scratch-and-sniff tests (scents varied from lemon to gasoline). People who weren’t as sharp odour identifiers also had markers of AD. Of course, this isn’t enough to diagnose you. If you’re worried about your risk, particularly if you have a family history of the disease, talk to your doctor. Find out 13 common illnesses that have been linked to Alzheimer’s.

Surprisingly, it may be one of several strep throat symptoms. If you have a little one who had a round of strep throat and has suddenly developed obsessive-compulsive tendencies, the culprit may be the group A Streptococcus infection. It’s a condition called PANDAS, or “paediatric autoimmune neuropsychiatric disorders associated with streptococcal infections.” Along with OCD, they may also develop anxiety, aggression or ADHD-like symptoms. It can be a difficult road to diagnosis, but there are several treatment options available. Talk to your child’s paediatrician if you notice an abrupt and alarming change in their behaviour and personality.