A 4-year-old boy presents to his pediatrician for severe developmental delay. On exam he is noted to have macroorchidism, hypertelorism, large protruding ears, a large jaw, and a long thin face. Suspicious of what the diagnosis may be, the pediatrician orders a PCR and DNA sequencing. The results reveal an expansion of 250 repeats of CGG. What is the diagnosis of the boy?

A 4-year-old boy is brought to the clinic by his parents for difficulty walking. He had an uncomplicated birth history and has been meeting his developmental goals. His mom reports that recently he has been using his arms and head to stand up and has been waddling more than usual. Physical examination was unremarkable except for the findings demonstrated in Figure A and a waddling, wide-based gait. What is the most likely pathophysiology of this child’s disease?

A 10-year-old boy with a history of progressive weakness presents to his primary care physician for annual check-up. He reveals that he has been finding it hard to walk over the last year and feels that he continues to get weaker. On physical exam, he is found to have large calves and when asked to stand he displays the behavior shown in Figure A (Gower’s Sign). If the gene responsible for his symptoms is dystrophin, what is the most likely inheritance pattern of this disease?

A 3-year-old boy is brought to the emergency department after having 4 days of a runny nose, low-grade fever, and general malaise. This morning, he started to experience shortness of breath with coughing and purulent sputum. The mother states that she is particularly concerned since the patient has already had 3 episodes of bacterial pneumonia during his lifetime, along with 2 episodes of viral gastroenteritis requiring hospitalization and intravenous fluids. On exam, the patient’s temperature is 101.0°F (38.3°C), blood pressure is 88/58 mmHg, pulse is 100/min, and respirations are 18/min. The patient is actively coughing, with crackles heard in the right lower chest. There are no palpable lymph nodes, but the exam is also notable for an absence of tonsils. After the patient is stabilized, blood testing and flow cytometry demonstrate the following:

IgA: Undetectable

IgE: Low

IgG: Low

IgM: Low

CD3 positive cells: Normal

CD19 positive cells: Low

Which of the following characterizes this child’s condition?

A pathologist performed an autopsy on an 18-month-old infant boy who died of pneumonia. Clinical notes revealed the infant had repeated respiratory infections that started after he was weaned off of breast-milk. Laboratory investigation revealed hypogammaglobulinemia and an absence of B-cells. T-cell levels were normal. Histological evaluation of an axillary lymph node revealed an absence of germinal centers. Which of the following is the mode of inheritance of the disorder that afflicted this infant?

You are seeing a 4-year-old boy in clinic who is presenting with concern for a primary immune deficiency. He has an unremarkable birth history, but since the age of 6 months he has had recurrent otitis media, bacterial pneumonia, as well as two episodes of sinusitis, and four episodes of conjunctivitis. He has a maternal uncle who died from sepsis secondary to H. influenza pneumonia. If you drew blood work for diagnostic testing, which of the following would you expect to find?

A 1-year-old boy presents to the physician with a fever and a persistent cough for the past 5 days. His parents noted that since birth, he has had a history of recurrent skin infections, ear infections, and episodes of pneumonia with organisms including Staphylococcus aureus, Pseudomonas, and Candida. Physical exam is notable for prominent facial scars in the periorbital and nasal regions, which his parents explain are a result of healed abscesses from previous skin infections. A sputum sample is obtained from the patient and the culture grows Aspergillus. Which of the following diagnostic test findings would confirm the patient’s underlying genetic disease?

Chronic Granulomatous Disease (CGD)

A 27-year-old man presents to his primary care physician because he has been experiencing increased fatigue and shortness of breath over the last two weeks. He says that he has a lot of stressors in his life currently because he just finished graduate school and moved to another city. The move was particularly arduous because he had an infection and also because the house was old and had a very narrow staircase. Due to this stress he has not been eating or sleeping well. On presentation his temperature is 98.6°F (37°C), blood pressure is 115/72 mmHg, pulse is 112/min, and respirations are 18/min. Physical exam reveals conjunctival pallor. A blood smear is obtained that is shown in Figure A (BITE CELLS/HEINZ Bodies) and lab tests reveals the following:

Hemoglobin: 11.2 g/dL

Mean corpuscular volume: 92 um^3

Which of the following interventions would be appropriate for the most likely cause of this patient's symptoms?

A 32-year-old man presents to his primary care physician because he has been experiencing fatigue and back pain over the last 2 days. He suffered from malaria after going on vacation 5 years ago and recently started taking a medication to deal with a latent form of this infection. He started developing these symptoms 36 hours after taking the first dose and noticed his urine became progressively darker during that time. On physical exam he is found to have scleral icterus and skin jaundice. Labs are obtained with the following results:

Hematocrit: 32% (Normal: 41%-53%)

Hemoglobin: 10.6 g/dL (Normal: 13.5-17.5 g/dL)

Leukocyte count: 8500/mm3 (Normal: 4500-11,000/mm3)

Platelet count: 273,000/mm3 (Normal: 150,000-400,000/mm3)

Which of the following would most likely be seen on a peripheral blood smear in this patient?

A 5-year-old African-American male with no previous medical history is taken to the ED by his mother because his urine was darker than normal. She notes that, for the past week, he has had a cough, runny nose, and fever. A few days ago, she gave him a small dose of acetaminophen, which seemed to help. This morning, he complained of worsening fatigue and back pain. When he went to the bathroom, his urine was the color of tea, prompting his mother to bring him to the hospital. In the ED, his vitals are as follows: temperature is 101.6 deg F (38.7 deg C), blood pressure is 120/80 mmHg, pulse is 99/min, respirations are 15/min. His exam is noteworthy for mild scleral icterus and mild splenomegaly. His labs are consistent with acute hemolytic anemia. Peripheral smear is shown in Figure A. What is the underlying cause of the patient's anemia?

A 5-year-old African-American male with no previous medical history is taken to the ED by his mother because his urine was darker than normal. She notes that, for the past week, he has had a cough, runny nose, and fever. A few days ago, she gave him a small dose of acetaminophen, which seemed to help. This morning, he complained of worsening fatigue and back pain. When he went to the bathroom, his urine was the color of tea, prompting his mother to bring him to the hospital. In the ED, his vitals are as follows: temperature is 101.6 deg F (38.7 deg C), blood pressure is 120/80 mmHg, pulse is 99/min, respirations are 15/min. His exam is noteworthy for mild scleral icterus and mild splenomegaly. His labs are consistent with acute hemolytic anemia. Peripheral smear is shown in Figure A. What is the underlying cause of the patient's anemia?

A 32-year-old Greek man presents with a rash consistent with dermatitis herpetiformis and is treated with a course of oral dapsone. Over the following several days he becomes increasingly fatigued and experiences persistent back pain. Complete blood count reveals a normocytic anemia, and urinalysis shows hemoglobinuria. Results from a peripheral blood smear are shown in Figure A. Which of the following is most likely responsible for this patient’s symptoms?

NOT A MEDBULLETS QUESTION:

X-Linked Recessive

Mutation of HPRT = increased Uric Acid and Hyperuricemia

Associated with Mental Retardation and Self Mutilation.

Disease?