Epilepsy Talk

Wrong diagnosis? | December 16, 2022

There are many ways that your medical care can go wrong. All of the phases from diagnosis to treatment can have some type of error.

Studies of error types: An Institute of Medical Report attempted to quantify the types of medical errors that occur in healthcare settings.

One cited study lists causes of errors as follows:

•Technical errors (44%)
•Misdiagnosis (17%)
•Failure to prevent injury (12%)
•Medication errors (10%)

About 70% of all errors were believed to be preventable. The remainders were presumably non-preventable errors such as a patient reacting to a drug who had no previous history of an allergy to the drug.

The National Patient Safety Foundation (NPSF) commissioned a phone survey in 1997 to review patient opinions about medical mistakes.

The findings showed that 42% of people believed they had personally experienced a medical mistake. In these cases, the error affected them personally (33%), a relative (48%), or a friend (19%).

Of these people, the type of mistake they had experienced was:

•Misdiagnosis (40%)
•Medication errors (28%)
•Medical procedure errors (22%)
•Administrative errors (4%)
•Communication errors (2%)
•Incorrect laboratory results (2%)
•Equipment malfunction (1%), and other errors. (7%).

Unfortunately, the wording in the study for misdiagnosis was “misdiagnosis or wrong treatment”, so it is unclear exactly how many were true misdiagnoses or wrong condition treated versus the wrong treatment for the correctly diagnosed condition.

In other questions, people reported that they believed their doctor failed to make an adequate diagnosis in 9% of cases, and in another question 8% cited misdiagnosis as a causal factor in the medical mistake.

The location where the medical error was experienced was:

•Hospital (48%)
•Doctor’s office (22%)
•Operating room (7%)
•Clinic (5%)
•Emergency room (5%)
•Pharmacy (4%)
•Home (3%)
•Medical laboratory (1%)
•Nursing home (1%), and others (5%).

When asked to cite what they believed primarily caused the error, NPSF survey respondents mentioned:

•Carelessness/negligence (29%)
•Untrained staff/incompetence (14%)
•Communication (12%)
•Misdiagnosis (8%)
•Overworked staff (8%)
•Misread prescription or pharmacy error (6%), and others (14%).

Diagnosis mistakes: There are various mistakes that can cause a misdiagnosis of a condition. Misdiagnosis can be one of the most costly of medical errors, leading to delayed, omitted, or inappropriate medical treatments.

•Self-diagnosis mistakes: when you diagnose yourself, mistakes are very common. Always seek professional medical advice. Do not rely on internet health information.
•Not diagnosed: some conditions are not obvious and may be missed, especially if they have no major symptoms.
•Wrongly diagnosed: you might be diagnosed as having the wrong condition.
•Wrong subtype of disease diagnosed: the diagnosis might have the correct overall disease, but the wrong subtype.
•Complications not diagnosed: the diagnosed disease may have various complications that also need to be diagnosed and treated.
•Underlying disease not diagnosed: there may actually be an underlying hidden disease causing the already diagnosed disease.
•Associated diseases not diagnosed: some types of conditions cluster together, even though they do not cause each other.
•Failure to diagnose others: infectious diseases need to be checked in family members and other exposed people; genetically associated diseases indicate family members may be at higher risk and may need screening.

Treatment mistakes: There are numerous ways that an error can occur in medical treatment.

•Self-treatment mistakes: if you try to treat yourself, mistakes are very common. Always seek professional medical advice.
•Wrong condition treated: misdiagnosis of the condition
•Wrong choice of treatment plan: the overall strategy used to treat your condition might not be the best one.
•Wrong type of treatment given
•Wrongly delayed treatment: there might be an undesirable delay in your treatment, by choice or through non-diagnosis.
•Wrongly performed procedures: all medical events such as surgeries and tests can have things go wrong.
•Wrong medications: see below.

Prevention mistakes: The failure to prevent a condition is another type of medical failing. In certain cases, it’s clear that preventive actions should be taken and failure to do so is a medical mistake.

•Failure to prevent known complications of a diagnosed disease.
•Failure to treat family members or others exposed to an infectious disease.
•Failure to address clear risk factors for various conditions

Surgery mistakes: Surgical procedures are often complex and subject to various errors.

•Surgery administration mistakes: wrong-patient, wrong-site, wrong-organ, equipment left inside.
•Surgical mistakes: the surgeon might make a wrong cut or other mistake.
•Anesthesia mistakes: too much, too little (waking up).
•Complications from surgery
•Infections from surgery: called “iatrogenic infections”
•Wrong blood type transfusion

Hospital mistakes: A hospital can make errors in any of its varied activities. There are many staff who can make human mistakes and overall system problems can also lead to errors.

•Hospital-caused infections: called “nosocomial infections”
•Medication errors in hospitals: ordered medication not given, wrong medication, wrong dosage, wrong combinations, wrong patient given medication, etc.
•Wrong procedures: failure to do ordered tests, wrong procedures or tests.

Medication mistakes: Errors in medication are a major source of medical mistakes. Medication errors can occur in hospitals or pharmacies, and the error may be made by any of the staff involved with choosing or dispensing medication.

•Inappropriate medication: the wrong medication given for a disease
•Wrong medication: the patient gets the wrong medication despite the doctor prescribing the correct one.
•Drug name mix-ups: several medications have similar-sounding names and can be mixed up by doctors or pharmacists.
•Wrong medication combinations: there are numerous types of medications that should not be mixed, because of side effects and cross-reactions when combined.
•Adverse reactions to medication: Some people have allergic or other adverse reactions to certain medications. These are risks and not necessarily avoidable mistakes if the person has no previous history of a particular adverse reaction.
•Side effects of medication: Almost all medications have some types of side effects. Some are mild, some nasty. It is almost impossible to know up front whether a person will have side effects from a medication.
•Non-compliance: the failure to follow your medication regimen can be a mistake made (usually by the patient).

Pharmacist errors: The dispensing of drugs by the pharmacy is a complex and busy activity. Various errors can occur at the pharmacist.

•Wrongly filled prescriptions
•Wrong drug supplied
•Wrong dosage supplied
•Drug name mix-ups: various drugs have similar names.

Pathology lab errors: Diagnostic testing done by a pathology laboratory can be subject to various errors. Some are administrative or human mistakes; other “mistakes” are inherent to the limitations of the type of test.

•Wrong biopsy results: visual inspection of cellular slides
•Administrative errors: mixing samples, etc.
•Known test errors and risks: almost all tests have a small percentage of unavoidable errors (false positives, false negatives).
•Known limitations of tests
Equipment failure errors: physical failures with medical equipment can occur.
•IV drips dislodged
•Dead batteries in equipment
•Unnecessary procedures
•Unnecessary tests
•Unnecessary visits

Medication errors: Mistakes in the use of a medication are one of the best tracked types of medical error. Errors with medication can occur in hospitals, at the pharmacy, in the doctor’s office, and even due to the patient.

Problems can include adverse reactions and interactions with other medications, and also basic administrative errors such as patients being given the wrong medication or wrong dosage. A less studied aspect of mistakes involving medications is the misdiagnosis of a disease when the real cause is a side effect of a medication; see medications underlying disease.

An Institute of Medical report gives detailed information about deaths and adverse events due to errors in medication. The report estimates that 7,391 deaths resulted from medication errors in 1993.

The IOM report cites one study finding that about 2% of hospital admissions experienced a preventable adverse drug event, although the majority are not fatal.

Medication error was cited as the cause of death for 1 in 131 outpatient deaths and 1 in 854 inpatient deaths.

Children and infants are particularly at risk of medication errors mainly due to incorrect dosage, because of the need to modify dosages based on age and weight. The dosage modification may be either overlooked or miscalculated. Various studies have shown high error rates in doctors and nurses in calculating weight-dependent dosages in infants and especially neonates.

Prescription errors: The dispensing of prescription medications at the pharmacy can have various errors. The wrong medication can be given, particularly when medications are named or packaged similarly.

There are particular drugs that are known to have problems because their names are very similar. The pharmacy can also give out the wrong dosage of the drug in some cases.

Most studies of medication errors only analyzed hospital medication usage, and there is a large volume of medications prescribed in doctor’s offices and dispensed by pharmacies.

There were nearly 2.5 billion prescriptions dispensed by pharmacies in 1998 in the USA compared to an estimated 3.75 billion drug administrations in hospitals. Errors in prescription and dispensing are known but difficult to quantify.

For example, the IOM report cites an Australian study for 1988-1996 finding that 2.4 to 3.6 percent of hospital admissions were due to medication events, of which 32 to 69% were preventable.

The medications causing most problems were cytotoxics, cardiovascular drugs, antihypertensives, anticoagulants, and NSAIDs.

Causes of prescription and medication errors included people with kidney conditions, liver conditions, or known drug allergies were at the greatest risk.

The Institute of Medicine (IOM) report cites the following factors as causal in medication errors:

•Failure to alter a medication or dosage due to patient’s reduced kidney or liver function (13.9%)
•Known allergy to same medication class (12.1%)
•Using the wrong drug name, dosage form, or abbreviation (11.4%)
•Incorrect dosage calculations (11.1%)
•Atypical or unusual and critical dosage frequency considerations (10.8%).

Data indicates the greatest risk in prescription errors was from the doctor rather than the pharmacist, with estimates as follows:

•Prescribing errors (68%)
•Administration errors (25%)
•Supply errors (7%).

Adverse drug reactions: An adverse drug reaction (ADR) is not necessarily a medical error although it can be. An adverse drug reaction occurs when a patient suffers a reaction, side effect, or other injury from a medication.

This can occur without an error, such as when a patient has an allergy to a medicine, but has never shown any signs or risk factors for this allergy previously. On the other hand, an error would occur if a previous allergy was known but the medication was still given to the patient.

Adverse drug reactions are quite common. It’s estimated that 6.7% of hospitalizations resulted in an adverse drug reaction, and 0.32% of cases were fatal. This averages out to about 2,216,000 cases annually in hospitalized patients and 106,000 deaths.

Studies estimate as many as 1 million patients are injured while in the hospital and approximately 180,000 die as a result. This leads to a cost estimate of more than $136 billion a year.

The article cites the list of medications most frequently causing adverse reactions in order of incidence:

•Antibiotics
•Chemotherapy
•Anticoagulants
•Cardiovascular agents
•Anticonvulsants
•Antidiabetic agents
•Antihypertensives
•Analgesics
•Antiasthma agents
•Sedative-hypnotic agents
•Antidepressants
•Antipsychotic agents
•Antiulcer agents.

Of course, mistakes are inevitable. (That’s why they’re called mistakes!) But take care and beware. Try to ensure these don’t happen to you.

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Resources:

https://www.improvediagnosis.org/what-is-diagnostic-error/

https://www.nolo.com/legal-encyclopedia/medical-malpractice-misdiagnosis-delayed-diagnosis-32288-2.html

https://www.verywellhealth.com/how-common-is-misdiagnosis-or-missed-diagnosis-2615481

https://www.fiercehealthcare.com/hospitals-health-systems/jhu-1-3-misdiagnoses-results-serious-injury-or-death

https://www.healthline.com/health-news/many-people-experience-getting-misdiagnosed

https://www.hopkinsmedicine.org/news/media/releases/diagnostic_errors_more_common_costly_and_harmful_than_treatment_mistakes

https://www.nationalepilepsytraining.co.uk/epilepsy-misdiagnosis-can-it-happen-and-how/

Information also supplied by:

To Err Is Human
Building a Safer Health System
Linda T. Kohn, Janet M. Corrigan, and
Molla S. Donaldson, Editors

Committee on Quality of Health Care in America
Institute of Medicine
National Academy Press
Washington, D.C.

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