Naevoid melanoma is a rare and dangerous type of skin cancer that looks deceptively harmless, often resembling an ordinary mole. This similarity makes it one of the most difficult melanomas to identify, which can lead to delayed diagnosis and treatment.

Naevus flammeus, also called a port wine stain, is a permanent birthmark that appears as a pink or red patch on a newborn’s skin. Named because it looks like wine has been spilled on the skin, this harmless mark is present in about 3 out of every 1,000 babies and grows with the child throughout life.

Narcolepsy is a chronic brain condition that disrupts the ability to control when you sleep and wake. People with this disorder often experience overwhelming sleepiness during the day and may fall asleep suddenly, along with other symptoms that can significantly affect daily life. While narcolepsy presents serious challenges, it responds well to treatment, allowing many people to manage the condition effectively.

Nasal and sinus cancer is a rare condition that develops in the space behind your nose or in the hollow air-filled spaces around it, often causing symptoms that may seem like ordinary sinus problems at first.

Nasopharyngeal cancer is a rare type of cancer that starts in the upper part of the throat, behind the nose. While uncommon in most parts of the world, it occurs much more frequently in certain regions of Asia and Africa. Early symptoms can be hard to recognize, but understanding this disease and its treatment options can help patients and their families navigate the journey ahead.

Recurrent nasopharyngeal cancer presents a difficult challenge for patients and their care teams, with treatment options depending on where the cancer returns and what therapies were used initially.

Neck pain is a widespread problem affecting millions of people, often caused by everyday habits like poor posture or stress, though it typically improves with simple treatments and self-care.

Necrotizing enterocolitis is a life-threatening intestinal illness that primarily strikes premature babies, causing inflammation and death of intestinal tissue that can lead to serious infection and requires urgent medical care.

Necrotising myositis is a rare inflammatory muscle disease where the body’s immune system attacks its own muscle cells, causing them to die. This leads to severe muscle weakness, particularly in the muscles closest to the center of the body, such as the shoulders, hips, and thighs.

Negative symptoms are a core component of schizophrenia that account for a large part of the long-term disability and poor functional outcomes in patients with the disorder. These symptoms describe a lessening or absence of normal behaviors and functions, and they can be just as disabling—if not more so—than the more dramatic symptoms like hallucinations.

Neonatal alloimmune thrombocytopenia is a serious blood disorder that occurs when a mother’s immune system attacks her baby’s platelets during pregnancy or shortly after birth. Although many cases are mild, this condition is the most common cause of severe low platelet counts in newborns and can lead to dangerous bleeding, including life-threatening brain hemorrhage.

Neonatal anoxia is a serious condition where a newborn baby’s brain and other organs are completely deprived of oxygen before, during, or shortly after birth, potentially causing permanent brain damage and lifelong disabilities.

Neonatal asphyxia is a serious medical condition where a baby does not receive enough oxygen before, during, or right after birth. This lack of oxygen can cause damage to the brain and other vital organs, leading to long-term health problems or even death. Understanding this condition is essential for parents and families facing its consequences.

Neonatal hyperglycaemia, or high blood sugar in newborn babies, is less common than low blood sugar but requires careful attention because it can increase the risk of serious health problems and even death in affected infants.

Neonatal respiratory distress syndrome is a serious breathing problem that primarily affects premature babies whose lungs haven’t fully developed, making it hard for them to get enough oxygen shortly after birth.

Neonatal respiratory failure is one of the most common reasons newborns need intensive care, affecting their ability to breathe properly and maintain normal oxygen levels in the first hours or days of life.

A neoplasm is an abnormal growth of tissue that forms when cells in your body grow and divide faster than they should, creating a mass that can be noncancerous or cancerous.

Malignant neoplasms are cancerous tumors that develop when cells grow and divide faster than they should, spreading to nearby tissues and distant parts of the body. Understanding this disease, its different forms, and available treatments can help patients navigate their diagnosis and care.

Neovascular age-related macular degeneration is a serious eye disease that can cause rapid vision loss when abnormal blood vessels grow behind the central part of your eye’s retina.

Nephroblastoma, commonly known as Wilms tumor, is the most common kidney cancer in children, typically appearing before the age of five and often first noticed as a painless lump in the abdomen.

Nephrogenic anaemia is a common blood condition that affects people with kidney disease, occurring when damaged kidneys cannot produce enough of a special hormone needed to make healthy red blood cells.

Kidney stones are hard masses made of crystals that form inside the kidneys and can cause severe pain as they move through the urinary tract. While small stones may pass on their own, larger ones may require medical procedures to break them up or remove them.

Nephropathy is a broad term for kidney disease or damage that can lead to serious health problems. While it affects millions of people worldwide, early detection and proper management can help slow its progression and protect your overall health.

Nephrotic syndrome is a kidney disorder where your body loses too much protein through urine, causing swelling and other health complications that require careful medical management.

Your nervous system controls everything you do—from moving and speaking to breathing and thinking. When something goes wrong with this complex network, it can affect your ability to work, learn, and enjoy daily life. With over 600 different disorders that can affect the nervous system, understanding these conditions is the first step toward getting proper care.

Netherton’s syndrome is a rare inherited disorder that affects the skin, hair, and immune system, presenting challenges from birth that can impact every aspect of daily life.

Neuralgia is a sharp, stabbing pain that follows the path of a damaged or irritated nerve. This condition can occur anywhere in the body and ranges from mild, temporary discomfort to severe, debilitating pain that significantly impacts quality of life.

Neuroblastoma is a rare cancer that develops in developing nerve cells and primarily affects young children, with most cases diagnosed before age 5. While this cancer presents unique challenges, advances in treatment have significantly improved outcomes, and some forms may even resolve without intervention.

When neuroblastoma returns after treatment or doesn’t respond to initial therapy, families face difficult challenges, but treatments and support are available.

Neurodegenerative disorders are chronic conditions that gradually damage and destroy parts of the nervous system, especially the brain, affecting more than 50 million people worldwide. While these conditions are permanent and incurable, many are now treatable thanks to medical advances, with current treatments focused on managing symptoms and slowing disease progression.

Neurodermatitis is a skin condition that creates an intense itch-scratch cycle, where scratching an itchy patch of skin makes it even itchier, leading to thick, leathery patches that can disrupt sleep, daily activities, and quality of life.

Neurodevelopmental disorders are a group of conditions that affect how the brain and nervous system develop, usually appearing in early childhood and potentially continuing into adulthood. These disorders can impact thinking, learning, communication, behavior, and movement, affecting millions of children and adults worldwide.

Neuroendocrine cancer of the prostate metastatic is a rare and aggressive form of prostate cancer that can develop when the disease spreads beyond the prostate gland and becomes resistant to hormone treatments.

Neuroendocrine carcinomas are fast-growing cancers that develop from specialized cells throughout the body, most commonly affecting the digestive system, lungs, and pancreas, with symptoms varying widely depending on where the cancer is located and whether it produces hormones.

When neuroendocrine tumors spread beyond their original location to other parts of the body, they become metastatic neuroendocrine cancer. While this represents an advanced stage of disease, many treatment options exist to manage symptoms, slow tumor growth, and help patients maintain quality of life for years.

Neuroendocrine carcinoma of the prostate is a rare and aggressive form of prostate cancer that develops when prostate cells change their behavior and stop responding to hormone-based treatments that normally control prostate cancer growth.

Neuroendocrine carcinoma of the skin is a rare and aggressive type of skin cancer that most often appears as a rapidly growing bump on sun-exposed areas of the body, particularly in older adults.

Neuroendocrine cell hyperplasia of infancy is a rare lung disorder that mainly affects babies and young children, causing rapid breathing and low oxygen levels in the blood, though most children gradually improve as they grow.

Neuroendocrine tumours are rare cancers that develop in specialized cells throughout the body, most commonly affecting the digestive system, lungs, and pancreas. While these tumours can be challenging to diagnose and manage, advances in treatment are helping more people live for years with this condition.

Lung neuroendocrine tumours are a rare but important group of cancers that develop in specialized cells within the lungs, with each type having its own characteristics, treatment approaches, and outlook for patients.

Neurofibromatosis is a group of genetic conditions that causes tumors to grow on nerves throughout the body. While most tumors are not cancerous, they can affect the skin, nervous system, eyes, and bones, causing a wide range of symptoms from mild skin changes to serious complications that require careful monitoring throughout life.

Neurofibrosarcoma is a rare cancer that grows in the protective covering around nerves. While the disease is uncommon, people with neurofibromatosis type 1 face a much higher risk of developing these aggressive tumors.

Neurogenic bladder is a condition that affects how your bladder works when there’s a problem with your brain, nerves, or spinal cord. While it cannot be cured, there are many ways to manage the symptoms and improve your quality of life.

Neuromuscular scoliosis is a sideways curve of the spine that develops in children who have conditions affecting their nerves and muscles. Unlike other forms of spinal curvature, this type often appears early in childhood and tends to worsen over time, affecting how children sit, stand, and move.

Neuromyelitis optica spectrum disorder is a rare autoimmune condition that attacks the nervous system, primarily affecting the eyes and spinal cord, and can lead to severe disability including blindness and paralysis if left untreated.

Neuromyopathy, commonly known as peripheral neuropathy, is a condition that affects nerves outside the brain and spinal cord, causing pain, weakness, numbness, and tingling—most often in the hands and feet.

Neuropathic arthropathy is a rapidly destructive joint condition that develops when damaged nerves prevent you from feeling pain and injuries in your joints. Without the warning signal of pain, repeated injuries can cause severe joint damage, deformity, and disability.

Peripheral neuropathy affects millions of people worldwide, causing damage to nerves outside the brain and spinal cord. This condition often leads to pain, numbness, and weakness, particularly in the hands and feet, significantly impacting daily life and quality of activities.

Neurotrophic keratopathy is a rare degenerative disease of the cornea that can lead to vision loss if left untreated. The hallmark of this condition is reduced or absent sensation in the cornea, making it difficult for patients to feel damage until the disease has progressed significantly.

Neutropenia is a condition where you have too few neutrophils in your blood, a type of white blood cell that helps your body fight infections. People with neutropenia are more vulnerable to infections because their body has fewer defenses against germs.

Nicotine dependence is a powerful addiction that affects millions of people worldwide, making it extremely difficult to stop using tobacco products even when people know the serious health risks.

Niemann-Pick disease is a group of rare inherited conditions that affect how the body breaks down and uses fats inside cells. When these fats build up in organs like the brain, liver, spleen, and lungs, cells stop working properly and eventually die, leading to serious health problems that worsen over time.

Waking up multiple times each night to urinate can disrupt your sleep and leave you exhausted during the day. This common condition, called nocturia, affects more than half of adults over 50 and can significantly impact your quality of life.

Nodal marginal zone B-cell lymphoma is a rare, slow-growing type of blood cancer that develops when white blood cells called B lymphocytes grow out of control in the lymph nodes.

Nodal osteoarthritis is the most common type of osteoarthritis, predominantly affecting women in their sixth decade of life, with a strong genetic component that influences which joints develop painful bony nodules.

Nodular melanoma is an aggressive type of skin cancer that grows quickly and deeply into the skin. Though it represents only 15% to 20% of all melanoma cases, it causes about half of all melanoma-related deaths, making early detection and treatment critical.

Non-cirrhotic portal hypertension is a rare condition where blood pressure increases in the veins that carry blood to the liver, without the presence of cirrhosis or liver scarring. Unlike the more common form of portal hypertension caused by advanced liver disease, people with this condition often have relatively preserved liver function despite experiencing serious complications.

Non-Hodgkin’s lymphoma is a group of cancers that develop in the lymphatic system, a network of vessels and glands that helps protect your body from infection and disease. When cells in this system grow out of control, they form tumors that can affect lymph nodes and spread to other parts of the body.

When Non-Hodgkin lymphoma returns after successful treatment or doesn’t respond as expected, it presents new challenges. However, many treatment options remain available, and doctors can often control the disease or even aim for a cure, depending on your specific situation.

When Non-Hodgkin’s lymphoma doesn’t respond to treatment or comes back after initial success, it presents significant challenges—but new therapies and approaches continue to offer hope for patients facing this difficult situation.