Chapter 1
A full-term baby girl is born to a 23-year-old G1P0 mother who did not seek prenatal care. The newborn turns blue shortly after birth; she also has a cleft palate. Within a few hours of birth, she develops muscle spasms. Lab evaluation reveals a low CD3 count and low ionized calcium
22q11.2 deletion syndrome also known as DiGeorge syndrome
A 68-year-old man presents for an annual physical examination. He reports mild fatigue for several months but attributes this to “just getting older.” Lab evaluation reveals microcytic anemia, undetectable ferritin, and thrombocytopenia.
Myelodysplastic syndrome
A 70-year-old man with a history of hypertension goes to his ophthalmologist for a routine eye examination. He has needed to wear eyeglasses while driving since he was 18 years of age. Ocular examination reveals increased intraocular pressure in both eyes. On a field test, there is significant loss of peripheral vision, and funduscopic examination reveals cupping.
open-angle glaucoma
A man in his 40s moves back to the United States from London and begins to feel depressed. He seeks help from a psychiatrist but withholds symptoms of memory loss. Following the onset of ataxia, he is referred to a neurologist. MRI reveals pulvinar sign. He dies 14 months later. Autopsy shows florid plaques.
Creutxfeldt-Jacob Disease (CJD)
A 5-year-old girl is taken to the pediatrician for evaluation of short stature. On physical exam she has multiple lower extremity bruises and bluish scleral discoloration. Dental exam reveals multiple cavities. Audiological evaluation reveals a conductive hearing loss. Radiographic skeletal survey reveals healed right seventh rib and right humerus fractures and a healing left midshaft clavicle fracture. The physician does not suspect child abuse.
Osteogenesis imperfecta
A 54-year-old college professor notices that his face appears red and swollen. Physical examination is also notable for distended veins in his neck. Chest x-ray shows a well-circumscribed anterior mediastinal mass with no evidence of local invasion, lung mass, or lymphadenopathy.
Thymoma
A 26-year-old woman presents to her primary care physician complaining of 1 year of heavy menses. On physical examination there are several red pinpoint macules on the buccal mucosa and there are ecchymoses on the extremities. Platelet count is 18,000/μL.
Immune Thrombocytopenic purpura
A 35-year-old man is involved in a ski accident in Colorado in the month of December. He returns home to Texas shortly thereafter, but begins to suffer from headaches. One day in January he tells his wife he cannot see, and she calls EMS.
Subdural hematoma
A 55-year-old man who was previously treated with radiation for head and neck cancer develops a new onset of headaches. He subsequently undergoes neuroimaging, and 2 parasagittal dural-based lesions are identified
Meningioma
A 47-year-old man presents to his primary doctor with 2 weeks of fever, headache, and muscle aches. He also has noted a nonpruritic erythematous rash in the right groin. The rash has been enlarging for the past week, with new areas of clearing resulting in concentric rings of erythema. The patient is a Boy Scout leader and recently returned from a camping trip in Connecticut.
Lyme Disease
An 8-year-old boy presents to the pediatrician with yellow eyes, pale skin, and dark urine. His mother states that he began having upper respiratory symptoms 2 days ago. She also states that her brother has similar episodes when he gets a cold. CBC is notable for normocytic anemia, elevated bilirubin, and negative fluorescent spot test. Peripheral blood smear reveals Heinz bodies and bite cells.
G6PD deficiency
A 50-year-old male smoker presents to the ED with a severe headache and dizziness. CBC is significant for hemoglobin 18.5 g/dL and urinalysis is positive for blood. Abdominal imaging reveals a renal mass.
Polycythemia as a paraneoplastic syndrome in renal cell carcinoma
A 43-year-old public health professor develops limb weakness and an ascending paralysis. She recently traveled to Haiti.
Guillain-Barre Syndrome
A 28-year-old man is in his second month of treatment for tuberculosis when he begins to experience cognitive difficulty at work. A few weeks later, he has a generalized seizure at his office. A coworker drives him to the hospital, where a brain CT shows several ring-enhancing lesions.
Toxoplasma encephalitis
A 45-year-old man presents to urgent care with 2 days of left knee pain, swelling, and erythema without recent trauma. He is afebrile. White blood cell count, ESR, and CRP are mildly elevated. Knee x-ray shows a large joint effusion but is otherwise normal. On further questioning he reports a similar episode of acute onset joint pain and swelling involving the right 1st metatarsophalangeal joint 3 years ago.
Gout
A 16-year-old boy presents with a high fever for several days. He also reveals that he has lost 10 pounds in the last 2 weeks. Physical examination reveals bilateral nontender lymphadenopathy. Imaging of the chest demonstrates a bulky anterior mediastinal mass.
Lymphoblastic lymphoma
The parents of a 4-year-old girl bring their daughter to the pediatrician because they are concerned about her fever, which has lasted for more than a week. Her parents have also noticed that she is less energetic and now walks with a limp. Physical examination is significant for hepatomegaly, scattered petechiae, and bruising over many surfaces of her body. Relevant laboratory findings include the following: Hemoglobin: 6 g/dL White blood cell (WBC) count: 25,000/mm3 Platelet count: 39,000/mm3 Peripheral smear: Many immature white cells with condensed chromatin, absent nucleoli, and scant agranular cytoplasm
Acute Lymphoblastic Leukemia
A 7-year-old boy presents to the doctor due to new onset of seizures. The mother reports that he has been falling down and “walking clumsily” for 6 months. He has also been performing poorly in school. The family history is uncertain due to adoption.
Huntington disease
A 40-year-old man begins to have attacks of dizziness that cause him to lie down in bed. The attacks are accompanied by nausea and vomiting. When he seeks help from his doctor, he reports that he has also been experiencing episodic fluctuations in hearing, as well as ringing in the right ear.
Meniere Disease
A 62-year-old woman presents with chronic left hip pain that is worse with activity. She has no history of trauma or malignancy. Left hip x-ray shows a bowing deformity of the proximal left femur, with expansion of the proximal femoral medullary space and proximal femoral cortical thickening. Lab evaluation reveals elevated alkaline phosphatase but normal serum calcium and phosphate. A nuclear medicine bone scan is performed to evaluate for other potential sites of involvement.
Paget disease
A 45-year-old woman presents to the ED with a spontaneous nosebleed. She reports 1 week of a fever that has not responded to acetaminophen. She denies cough, shortness of breath, abdominal pain, dysuria, and rash. Physical examination is notable for active bleeding from the nares bilaterally and numerous pinpoint red papules on her lower extremities. Lab evaluation reveals elevated white blood cell count, low hemoglobin/hematocrit, and low platelets.
Acute myelogenous Leukemia
A 13-year-old boy is brought to his physician for increasing abdominal distention and pain that has lasted 7 days. Physical examination reveals decreased bowel sounds, tympany, and lower abdominal tenderness. CT scan of the abdomen shows a 6-cm mass involving the distal ileum. A biopsy of the mass is taken under radiographic guidance. The histologic sample shows sheets of intermediate-sized lymphoid cells with nonconvoluted nuclei and coarse chromatin along with many macrophages
Burkitt lymphoma, a highly aggressive B-cell non-Hodgkin lymphoma.
A 75-year-old woman visits an ophthalmologist because she has noticed a gradual decline in both her distance and near vision during the past 2 years. In particular, she has difficulty reading, focusing on objects in front of her, and adjusting her vision to the dark. She denies pain in her eye or any associated trauma. Funduscopic examination reveals deposits in the macula and abnormal vision as assessed by the Amsler grid. Her peripheral vision and extraocular movements are intact
Age related macular degeneration
A 5-year-old boy is brought to the pediatrician by his mother for a follow-up appointment. Two months ago, the boy was seen for a chief complaint of morning headaches, vomiting, and decreased energy. A gastrointestinal illness was suspected. At this visit, the mother reports that her son’s symptoms have worsened and that he now is falling and has a stumbling gait.
Medulloblastoma
A 22-month-old child presents with abnormal bowing of the legs and difficulty walking. He was exclusively breastfed until age 12 months. He lives in a cold climate with limited exposure to direct sunlight. Physical exam reveals bowlegs, wrist soft tissue swelling, and open anterior fontanelle. Wrist x-ray shows osteopenia with cupping and fraying of the distal radial metaphyses
Rickets