Delayed Diagnosis

Getting diagnosed with an illness, disorder, or disability seems easy enough; you just go to a doctor/therapist, they give a diagnosis based on the symptoms you're experiencing, and you can get treatment to cure it or make it more manageable. Unfortunately, it's much more difficult in real life than one might think. People suffering from an illness or a disorder won't always find out about it the first time around, and they may not discover what they have until months or even years later.

There are several reasons why this happens:

• Their symptoms are minor (oftentimes initially before they start to get worse); if they go to a doctor/therapist, then they'll be told that it's nothing serious.
• The character is misdiagnosed because the symptoms are similar to that of another illness.
• The character does not have adequate access to healthcare, either because there are not any doctors nearby or because they can't afford it.
• The setting takes place in a place or time period where the condition is not officially recognized yet.
• The condition is very rare with only very few people having and being diagnosed with it; most doctors may not be aware of the condition as a result.
• The character is a child and people think that they can't have that illness. Truth in Television, as many people think that it's not possible for children to have certain illnesses or disorders due to it being uncommon for them to have them.
• The doctor or therapist is incompetent at their job and, if they're mean-spirited enough, may even deliberately not diagnose the character with the correct illness/disorder.
• Everyone thinks that they're Playing Sick. This is common with people who have Hypochondria (A disorder that causes people to have anxiety over their health) who actually do get sick, but their past worries cause people to think that they're just freaking out over nothing again.
• The character refuses to go get their symptoms checked out, likely due to a fear of doctors and hospitals.
• The character doesn't realize that some of their symptoms are abnormal in the first place, so they don't see a reason to bring them up with their doctor.

Due to not getting an accurate answer, the character will continue to suffer from the condition that they don't even know they have. When they finally get a proper answer to their problems, they will be relieved to know what's wrong with them so that they can get treated for it. Alternatively, the disease is at a stage where it is no longer able to be treated, which may cause the patient to die. This has happened a lot in real life with people who found out they had a serious illness later in life, only to be told, at that point in time, it is no longer treatable.

Can also apply to Fictional Disabilities. Compare Incurable Cough of Death, which may overlap. See also Lethal Diagnosis when the character only shows symptoms of the disease after they are diagnosed, Definitely Just a Cold when a character brushes off serious symptoms and thinks that their illness is minor, and Diagnosed by the Audience, an Audience Reaction when it isn't clear what condition the character has to both other characters and the audience.

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Examples:

Comic Books

• In Ant-Man, Hank Pym showed signs of some mental illness for years before it was finally revealed that he was bipolar.

Fan Works

• In The Death of Dax, which is a Star Trek: Deep Space Nine fanfiction, Dax dies because she had a serious illness which the doctor misdiagnosed as flu. Some of the confusion came from the fact that Dax is an alien.
• In The One to Make It Stay, Luka was diagnosed with autism as a kid. Before he was diagnosed, he would lash out more often at things like losing a game to his sister or if his mom didn't have time to play guitar with him. His mother initially dismissed these outbursts as a phase young children go through until his temper issues went on for way too long. That was when she suspected that something much more complex was going on and brought him to mental health specialists. He mellowed out after a few years of therapy and learning to meditate.
• In the NUMB3RS story Collateral Damage, Don is feeling sick in the first part of the story, believing that it's food poisoning from the previous day. In reality, he is suffering from a ruptured appendix, which is finally diagnosed after getting into a car accident while chasing a suspect.
• With Pearl and Ruby Glowing:
  • Zuko was diagnosed with autism in the 90s when he was in his sixties because the disorder wasn't really known about before then.
  • Mulmangcho escaped from North Korean captivity, and in the hospital, he found out he has intermittent explosive disorder. He would have never been able to join the military and subsequently get tortured had a psychologist caught it before, so he wasn't happy.
  • Bidoof has Sensory Processing Disorder, but didn't know because everyone would call her "stupid" for not understanding others. It's only after she's taken away from her abusive mother that she learns that she has it.
  • Sid was sent to The Gulag for being visibly disabled, but they didn't know the specifics until after he escaped and was diagnosed specifically with Waardenburg Syndrome.
• Bait and Switch (STO): In "Tinker Golfer Doctor Trill", the Riyannis symbiont's first host Chiga has a bit of Attention Deficit... Ooh, Shiny! about her, jumping between topics without much break; current host Birail recalls having a short attention span but also often hyperfocusing when she was working a problem. "Trill Disjoined", written several years later, confirms explicitly that Chiga "had an attention deficit disorder".
• Manehattan's Lone Guardian sees Gray Ghost, a pony with a very cat-like mentality. Leviathan believes that those habits stem from an un-diagnosed mental problem. Gray herself explains that she's tried visiting several doctors in the past to figure out what the problem was, but that her idiosyncrasies were too much of a turnoff to them for her to get a proper diagnosis. It isn't until well into adulthood—roughly thirty-four years after she started showing these habits—that she discovers that her disorder was brought about unintentionally by an outside party, putting the matter to rest.

Film — Animated

• In Mary and Max, it took Max until 1980, when he was in his 40s, to be diagnosed with Asperger's Syndrome.

Literature

• The memoir Look Me in the Eye: My Life with Asperger's by John Elder Robison describes the author's life from the 1960s through the 1990s, with Asperger's Syndrome not being formally recognized for the vast majority of that period (it achieved that status in 1994). Throughout his childhood, Robison struggled to fit in due to the people around him not understanding what was wrong with him, instead writing him off as just difficult. He was finally diagnosed in 1996 at the age of 39.
• In Death Star, stormtrooper Nova Stihl goes to get checked out for his upsetting and consistent dreams, which are generally about ways he may die going about his duty. A doctor, Uli, finds the only irregularity that comes up is that Nova's got an unusually high midichlorian count, twice the human average. Uli started practice before the rise of the Empire and in fact served alongside a Jedi healer, so he knows that there's an association between midichlorians and strange dreams, but also that most research in the area was done by Jedi and that data is heavily restricted now. As a good doctor who wants to investigate all avenues Uli still puts in a query for information and sends Nova off with a prescription for sleeping pills. Months later when the query finally makes it through the queue... Uli is arrested for forbidden research, since The Empire is just that harsh about anything connected with the Jedi.
• Played for Drama In World War Z. "Quisling" becomes viewed as a mental health condition, where a person has a mental break and begins imitating zombies despite being alive. Unfortunately they were viewed as "real" zombies by the population at large for months, which caused the mistaken belief that a drug used to "treat" and cure zombies worked. It didn't, but it took all that time to understand that small but significant numbers of people were suffering from a mental health condition and not zombification.

Live-Action TV

• Played with in American Horror Story: Roanoke, where one overly-optimistic historian speculates that deranged nobleman Edward Phillippe Mott had severe social anxiety. Considering that he killed his entire household because someone destroyed his collection of paintings, social anxiety probably doesn't explain all of his problems.
• Boston Legal: Character Jerry Espenson is revealed to have Asperger's syndrome, which he didn't find out he had until he was an adult when Alan Shore is trying to come up with a defense after Jerry took Shirley hostage after being passed over for partner.
• In season 3 of Crazy Ex-Girlfriend Rebecca is finally diagnosed with borderline personality disorder, well into her 20s and long after she began exhibiting signs of mental illness. That's because, before then, she had been diagnosed with a number of other things such as anxiety and sex addiction, none of which got to the root of her problems.
• Subverted in Girl Meets World. Farkle is socially awkward, intelligent, obsessive, and even got bullied for being "weird". Then came "Girl Meets Autism"- when he learns about the disorder and its symptoms, he begins to fear that he has it because it fits some of his notable quirks. In the end, however, he and his parents discovered that he's not Autistic after all, despite his oddities. His love interest Smackle, on the other hand, was revealed to have been diagnosed since childhood.
• In Girls, Hannah is diagnosed with OCD in Season 2 after having a prolonged breakdown over the whole season. However, there were subtle hints that she was mentally ill before that; in Season 1, during their huge fight, Marnie reveals that Hannah masturbated compulsively as a teenager to "stave off diseases of the mind and body."
• A two-part episode of The Golden Girls had Dorothy experience extreme exhaustion, but her doctor tells her that her symptoms are all in her head. She later sees a specialist at the recommendation of another doctor, who diagnoses her with chronic fatigue syndrome. When Dorothy sees her first doctor at a restaurant, she tells him off for not taking her symptoms seriously. This episode was partly based on show creator Susan Harris' experiences with not being taken seriously by medical professionals (she suffered from adrenal issues, which have similar symptoms to CFS).
• In the first season of Hannibal, Will Graham begins sleepwalking, having hallucinations, and various other symptoms which could be physical or mental. Dr. Lecter, whose keen sense of smell diagnoses two other patients in quick succession, reacts to Will's scent but doesn't comment. When Will finally decides to get tested for a physical cause, a brain scan reveals an autoimmune encephalitis, but Lecter convinces the doctor running the scan to fake normal results so that they can observe the progression of the disease. Will goes undiagnosed for several more episodes, until another psychiatrist gets involved, but by then Lecter has already used Will's erratic behavior to frame him as a serial killer.
• The premise of House. Dr. House and his team have to deal with the Patient of the Week and figure out what's wrong, going through several possibilities that only end up incorrect. They only figure out the real problem by the end of the episode, and usually it is partly the fault of the patient for the misdiagnosis because sometimes the patient lies about their lifestyle or withheld information they thought was irrelevant.
• The Law & Order: Criminal Intent episode "Probability" deals with Wally Stevens, a mild-mannered, middle-aged accountant who fell into crime because his odd behaviors repelled people and made it difficult for him to hold down a regular job. When Goren suggests that he might have Asperger's syndrome (which, at the time, had only been recognized for maybe a decade or so), he's almost relieved that there's a name for it.
• The Gang in It's Always Sunny in Philadelphia is a group of unhinged comedic sociopaths, but Dennis is the only one who's been explicitly diagnosed within the show as having Borderline Personality Disorder in Season 10, and only because he was attempting to con a psychiatrist but answered all of his questions honestly. His sister Dee tries to get him to take his diagnosis seriously, but he's too much of a narcissist to entertain the idea of there being anything wrong with him.
• My Left Nut: Patricia dislikes doctors because she claims they act enigmatically about diagnosis until they're 100% certain, which can make families suffer needlessly.
  Patricia: We'd been in and out of here for months. Doing tests and tests and more tests. And they never said what was wrong. So one day your dad just says to them: "Is it motor neurone disease" 'cos I think he kinda knew. But the doctor wouldn't say. So Jimmy plagued him and plagued him and the doctor still wouldn't say even though it was pretty obvious because the junior doctor was sitting crying. And eventually Jimmy turned around and says, in your opinion, is it motor neurone disease, and the doctor says yes.
• Happens in every episode of Mystery Diagnosis, which deals with real-life cases. The basic formula is that the person in focus is suffering from strange symptoms. The doctor diagnoses them with an illness that matches the symptoms, but the problems persist and get worse. By the end of the episode, the character will get an accurate diagnosis. For most of these cases, the conditions that the patients really had were extremely rare and mostly unknown.
• In the BBC adaptation of the Miss Marple book "4:50 From Paddington", one of the Crackenthorpe family has a terminal illness that the local doctor didn't diagnose until it was too late. This turned out to be entirely deliberate on the doctor's part.

Video Games

• A variation in Night in the Woods. Mae Borowski suffered from a mental break when she was fourteen and beat another kid with a baseball bat. The local doctor is decidedly a Master of None Jack of All Trades but is especially terrible at mental health, so instead of giving Mae an actual diagnosis, he gives her a journal and nothing else. Since her symptoms are described as seeing everything as "just shapes", it's heavily implied that she has some form of dissociative disorder or psychosis. Mae, unfortunately, never truly gets an answer to her mental issues.
• In Red Dead Redemption II, the main character, Arthur Morgan, contracts tuberculosis during the mission "Money Lending and Other Sins", but isn't officially diagnosed until near the end of the game and ultimately passes away from his illness.

Webcomics

• In Dumbing of Age, Joyce is a college student before her opthamologist suggests she should probably look into getting tested for autism, after she covers for her nervousness by getting deep into her St Paul obsession. It's implied that her conservative religious upbringing would have discouraged ideas like that. By contrast, Dina's parents have repeatedly tried to get her an autism diagnosis, but the psychologists they see keep saying her apparent symptoms are actually just because English isn't her first language, even though it is.
• In Foxes in Love, Green is shown to be impulsive and easily distracted, which is later revealed to be due to ADHD in a 2022 comic where his doctor formally diagnoses him.

Web Original

• Far too many examples at Not Always Healthy. For instance, we have this case of a patient with a rare but not that rare form of epilepsy being "diagnosed" with a learning disability.
  • And over at Not Always Learning, this account of a woman with undiagnosed dyslexia.

Real Life

• There are many diseases that have similar symptoms to other diseases but are much worse. If you go to the doctor complaining of these symptoms, chances are you're going to initially be diagnosed with the less serious one.
• Many forms of Autism Spectrum Disorder, particularly the kinds viewed as "higher functioning," weren't defined in medical texts until the 1990s or later; this has resulted in many adults not being diagnosed until fairly late in life (Anthony Hopkins, for instance, remained undiagnosed until age 70). It's not unheard of for parents to go to a neurologist to have their children evaluated only to find out that they, too, are on the spectrum.
  • Most autistic girls aren't diagnosed early on because the majority of research on autism is done on male subjects; most recognized symptoms/traits/idiosyncrasies that stick out in boys either line up too closely with female gender norms or are easy for autistic girls to mask.
• Many symptoms of learning disorders such as ADD/ADHD and dyslexia are often ignored because people will assume that the person is just being "lazy" when they really are trying their hardest.
• At the beginning of the COVID-19 Pandemic, there have been some reports of delays for tests for people, due to a short supply and the tests taking a few days to even confirm, which allowed the virus to further spread. Misdiagnosis has also been a problem; early symptoms of COVID are very close to symptoms of the common cold, and because the first cases were reported in December of 2019, many areas got their first COVID exposures during cold and flu season.
• Cats are very good at hiding illnesses; it's entirely possible to not even realize your four-legged friend is sick until it's too late. This also happens with any pet that's a prey animal, too.
• Although HIV was present among humans since the 1950s (the earliest HIV-positive blood samples were from 1959 Léopoldville — today, Kinshasa) and is estimated to have first emerged in the 1920s, it wasn't first noticed until 1981 (by which point it had already spent at least four years infecting people in the west), and the actual virus wasn't officially detected for another two years. It helps that AIDS doesn't kill by itself but by the opportunist diseases, such as tuberculosis, brought by the weakening of the immunity.
• Hypermobility disorders can end up not being noticed until at least adulthood because the affected doesn't realize that their range of motion is not normal.
• Many women with endometriosis, a painful disorder of the reproductive system in which endometrial cells improperly grow outside the uterus, will have to try for years before they get a diagnosis because the primary symptom is abdomen pain during menstruation. Combined with the Hysterical Woman stereotype, it's consequently often difficult for them to convince doctors that what they're experiencing is more than just typical cramping (if they aren't outright dismissed as a plea for attention).

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