Steve is a previously healthy 25-year-old self-employed construction worker. He presents to the emergency department with a 3-month history of progressive lethargy, decrease in appetite, unintentional weight loss of close to 18 kg, dry cough, fever and drenching night sweats. He also has canker sores in his mouth. Steve has been taking close to the daily maximum amount of acetaminophen for the fevers. Aside from a camping trip in Belleville, Ontario, 7 months prior to this visit, he hasn't travelled anywhere.
Though he's pale and cachectic, Steve's vitals are normal. There's no pain, no nausea, vomiting or diarrhea. On exam, the oral mucosa looks normal, there are no petechiae, the sclera are unremarkable and there's no cervical lymphadenopathy. The abdomen is soft with no noticeable organomegaly. There's no bruising evident on the skin. Both the musculoskeletal and neurologic exams are unremarkable.
Blood work comes back revealing a pancytopenic picture. The hemoglobin is 93 g/L with normal indices, white blood cell count is 1.9 x 109 cells/L and platelets are 103 x 109/L. The blood smear is normal, as is partial thromboplastin time (PTT). The international normalized ratio (INR) is 1.2. Liver function tests are slightly elevated, however, in particular bilirubin, aspartate aminotransferase (AST) and lactic dehydrogenase (LD). Screens for hepatitis A and B, as well as HIV, are negative. Thyroid-stimulating hormone level is normal.
An alarming CT scan
A CT scan of the chest, abdomen and pelvis with contrast shows splenomegaly
(18 x 16.5 cm) and adenopathy in the axillary, subcarinal, and retroperitoneal
areas suggestive of lymphoma. The following day, the oncologist
performs a bone marrow aspiration. Unpredictably, it's not consistent
with malignancy.
Instead, it shows granulomatous inflammation. A bone gallium scan demonstrates prominent uptake in the pelvic girdle, proximal femurs and proximal humeri. Over the next 4 weeks, Steve requires numerous blood transfusions because his hemoglobin plummets to a precarious 57 with no evidence of a gastrointestinal bleed.
What's the next step?
What's the reason for Steve's transfusions?
Diagnosis
Although the initial blood and bone marrow cultures were found to
be negative, certain aspects of the case suggest a fungal infection:
- granulomatous changes in the bone marrow
- pattern of uptake on the gallium scan
The presumptive diagnosis is histoplasmosis, which was likely transmitted during the demolition of a cottage north of Toronto. Bone marrow cultures are being repeated and will take several more weeks for confirmation.
Management
In the meantime, Steve is initiated on an oral antifungal, itraconazole.
The length of treatment is 6 months.
Etiology and risk factors
Histoplasmosis is a disease caused by the fungus Histoplasma
capsulatum. Its symptoms vary greatly, but the illness primarily
affects the lungs. Occasionally, the disease spreads to other organs
as well, as evidenced in Steve's case. Certain features show up
on the chest x-ray and CT in disseminated histoplasmosis, but Steve's
lungs weren't affected in the typical way. In fact, his chest x-ray
and lung CT were both clear.
H. capsulatum grows in soil and material contaminated with
bat or bird droppings. Spores become airborne when contaminated
soil is disturbed. Breathing the spores causes infection. People
who work with dirt, birds, or bats are the most at risk. This includes
farmers with chicken coops, construction workers, and gardeners
who use chicken manure.
Although the disease is most often very mild - no worse than flu
- if left untreated, a later complication could include ocular histoplasmosis
syndrome, a leading cause of macular vision loss in young adults.
Pericarditis may develop in 10% of symptomatic patients.
We'll send you $100 if we print your diagnostic challenge. Send case description (app. 450 words) with final diagnosis and outcome to: parkex@parkpub.com.
- Why the upper back and bilateral shoulder pain?
- For want of a nail…
- Photos, facts and fibs... Little monsters
- Dizzy and fainting
- What’s the cause of this lady’s chronic wrist pain?
- Photos, facts and fibs... Hair today, gone tomorrow
- Blood count in free fall
- What’s the cause of this woman’s chest x-ray abnormality?
- Photos, facts and fibs... Rash decisions
- What do the renal and hepatic findings in this patient indicate?
- Why do I have a slow heart rate?
- Photos, facts and fibs... Hand signals
- What’s causing this woman’s neck mass?
- Not a big enough jerk
- Test your knowledge of the heart with this quick quiz
- ECG Strip Tease
- Multiple clots have a common cause
- What’s causing the abnormality on this woman’s mammogram and breast MRI?
- Photos, facts and fibs... eyes reveal signs of the condition
- What’s causing this man’s foot pain?
- Why are Mrs. J.P.’s legs swollen?
- How much do you know about Parkinson’s disease
- Photos, facts and fibs... lumps, bumps and lesions
- Why is Mrs. D.’s stomach pain getting worse?
- What’s causing this teenager’s scrotal discomfort?
- Photos, facts and fibs... four morbiliform rashes
- Why did this man collapse on the bus?
- Photos, facts and fibs
- What’s the cause of this lumbar CT abnormality?
- Stars of ill omen
- What’s causing this medial right lung mass?
- Not fit for a stress test?
- What caused the abnormal shadow on a chest x-ray?
- Test your knowledge on ankylosing spondylitis and ectopic pregnancy
- Gait disturbance reveals skeletal malformation
- What’s causing the knee pain?
- How much do you know about… Chronic fatigue syndrome
- Asthma exacerbation won’t go away
- How much do you know about... Lupus
- What’s the cause of this chest x-ray abnormality?
- What’s causing the pelvic pain?
- Headache and moodiness
- How much do you know about Oral contraceptives part 2
- What’s causing this patient’s persistent right leg pain?
- Why am I losing weight, Doc?
- How much do you know about… Oral contraceptives
- What’s the incidental finding on this CT scan?
- Constipation relief turns to grief!
- How much do you know about… Endometriosis
- Why is this man’s body swelling?
- What’s causing this woman to waste away?
- Worth cancelling a holiday?
- How much do you know about…
Sjögren’s syndrome - Why the burning sensations in the arms?
- A pain in the thigh
- Why is the epigastric pain worsening?
- How much do you know about... Infections in pregnancy
- What’s the reason for the headache?
- Unsteady on his feet
- The building-business blues
- What’s causing the foot swelling?
- Rising lipids trump executive
- Ex-cop brought down by cough
- What's the cause of the seizures?
- Growing edema and shortness of breath
- "Not another sore throat!"
- Why the hearing loss?
- Salter-Harris classification for growth plate fractures
- A "flu" that's hard on the liver
- Upper GI barium series, what’s your call?
- Perplexing lack of pain
- Abnormality of CT scan, what’s your call?
- Unexplained anxiety
- What a sneeze!
- From diarrhea to disability
- Too healthy to be ill
- Riling rash
