What's Your Diagnosis?

10-year-old female presents with severe respiratory distress

A previously healthy and fully immunized 10-year-old female presented to her local clinic for evaluation of a recent febrile illness with cough, sore throat and difficulty breathing. A rapid strep test was negative, but she was empirically treated with amoxicillin and prednisone anyway, which had no benefit, and within 2 days, she was in respiratory distress with a higher temperature.

James H. Brien
Theresa Madigan

She was admitted to the local hospital with the diagnosis of community-acquired pneumonia and asthma. Her antimicrobial therapy was changed to ceftriaxone and azithromycin, with bronchodilator therapy and IV methylprednisolone. Her admitting complete blood count (CBC) revealed 5.3 white blood cells (WBCs) and 87,000 platelets, and her chest radiograph showed moderate bilateral perihilar and interstitial infiltrates with bilateral pleural effusions (Figure 1).

Source: Theresa Madigan, MD

Chest radiograph, day 3 of illness.
Day 4 of illness.
Day 5 of illness.

Within 24 hours, her respiratory distress had worsened, requiring transfer to a children’s medical center pediatric ICU, where she was placed on a conventional ventilator that soon was changed to a high-frequency oscillator to maintain adequate oxygenation (Figure 2). She also developed hypotension and disseminated intravascular coagulation (DIC), requiring vasopressors and blood products. Her empiric antimicrobial therapy included Zosyn (piperacillin-tazobactam, Pfizer), vancomycin, azithromycin and amphotericin B. During this time, her WBC count rose to 77.9, and she further deteriorated, requiring emergent extracorporeal membrane oxygenation (ECMO), necessitating transfer to a tertiary care center. Bilateral chest tubes were placed, producing a large volume of serosanguinous fluid. By this time, she had developed severe generalized edema (anasarca) (Figure 3).

Multiple blood cultures, sputum and pleural cultures were negative. A bronchoalveolar lavage (BAL) culture grew a few colonies of pan-sensitive Pseudomonas fluorescens, with fungal, viral and mycobacterial cultures and testing negative. Other negative testing included HIV, Interferon-gamma release assay, Legionella, Histoplasma, Blastomyces, Aspergillus, Coxiella burnetii, Sporothrix schenckii, RVP, Bordetella pertussis Epstein-Barr virus (EBV) and cytomegalovirus (CMV). However, the IgG/IgM screen for Hantavirus was positive, with confirmatory testing pending.

The patient lives on a North Dakota Native American reservation with her parents and siblings, with no sick contacts. She had no history of travel, and the only animal exposure was to healthy family dogs. Interestingly, about 2 weeks before the onset of her illness, a tornado had damaged the roof of the family home, exposing old insulation material.

What’s your diagnosis?

A. Sin Nombre virus

B. Hantavirus

C. Four Corners virus

D. Pseudomonas fluorescens

pneumonia

Case Discussion

The answer can be A, B or C. The confirmatory Hantavirus IgM returned positive for the Sin Nombre virus, confirming the diagnosis of Hantavirus cardiopulmonary syndrome. There are more than 50 species of the genus Hantavirus, including Sin Nombre (or “no name”) virus, also known as Four Corners virus, the one responsible for most infections in the Four Corners area of the Southwest, where Colorado, New Mexico, Utah and Arizona come together. The deer mouse is the vector there. Other species of mice may carry different species of the Hantavirus in other areas of the country and world, but this region is where the disease was first recognized and studied when there was an outbreak in 1993. That year, the weather conditions favored a much larger than usual population of deer mice, thereby increasing the chance of spread. Hantavirus cardiopulmonary (HCP) syndrome usually results from inhaling the aerosolized urine or excrement containing the virus. In this case, the exposure likely came from aerosolized virus created by the tornado that swept through the area.

The incubation period is between 1 to 8 weeks, and the early clinical symptoms include flu-like complaints with fever. Within a week, the patient progresses into more severe respiratory distress with cardiogenic shock, requiring intensive care, where the mortality rate can still be up to 35%.

Day 14 of illness.

Although a small amount of Pseudomonas fluorescens was recovered from the BAL, this organism would not be the best explanation for the clinical picture of bilateral, diffuse lung disease with shock and DIC, with negative blood cultures, in a patient with community-acquired pneumonia with no indication of immune deficit or chronic lung disease. This most likely represented a small amount of contamination.

After 4 days on ECMO, the patient transitioned to a conventional ventilator for 2 more days and was then extubated. She rapidly improved, with resolution of all abnormal symptoms and findings, and she was discharged in good health on day 14 of her illness (Figure 4). This case represents the 14th confirmed case of HCP syndrome in North Dakota. A site investigation failed to find any rodents in the family home.

Disclosure: Brien reports no relevant financial disclosures.

I would like to thank Theresa Madigan, MD, pediatric infectious diseases fellow, Mayo Clinic, Rochester, Minnesota, for serving as guest contributor.

A previously healthy and fully immunized 10-year-old female presented to her local clinic for evaluation of a recent febrile illness with cough, sore throat and difficulty breathing. A rapid strep test was negative, but she was empirically treated with amoxicillin and prednisone anyway, which had no benefit, and within 2 days, she was in respiratory distress with a higher temperature.

James H. Brien
Theresa Madigan

She was admitted to the local hospital with the diagnosis of community-acquired pneumonia and asthma. Her antimicrobial therapy was changed to ceftriaxone and azithromycin, with bronchodilator therapy and IV methylprednisolone. Her admitting complete blood count (CBC) revealed 5.3 white blood cells (WBCs) and 87,000 platelets, and her chest radiograph showed moderate bilateral perihilar and interstitial infiltrates with bilateral pleural effusions (Figure 1).

Source: Theresa Madigan, MD

Chest radiograph, day 3 of illness.
Day 4 of illness.
Day 5 of illness.

Within 24 hours, her respiratory distress had worsened, requiring transfer to a children’s medical center pediatric ICU, where she was placed on a conventional ventilator that soon was changed to a high-frequency oscillator to maintain adequate oxygenation (Figure 2). She also developed hypotension and disseminated intravascular coagulation (DIC), requiring vasopressors and blood products. Her empiric antimicrobial therapy included Zosyn (piperacillin-tazobactam, Pfizer), vancomycin, azithromycin and amphotericin B. During this time, her WBC count rose to 77.9, and she further deteriorated, requiring emergent extracorporeal membrane oxygenation (ECMO), necessitating transfer to a tertiary care center. Bilateral chest tubes were placed, producing a large volume of serosanguinous fluid. By this time, she had developed severe generalized edema (anasarca) (Figure 3).

Multiple blood cultures, sputum and pleural cultures were negative. A bronchoalveolar lavage (BAL) culture grew a few colonies of pan-sensitive Pseudomonas fluorescens, with fungal, viral and mycobacterial cultures and testing negative. Other negative testing included HIV, Interferon-gamma release assay, Legionella, Histoplasma, Blastomyces, Aspergillus, Coxiella burnetii, Sporothrix schenckii, RVP, Bordetella pertussis Epstein-Barr virus (EBV) and cytomegalovirus (CMV). However, the IgG/IgM screen for Hantavirus was positive, with confirmatory testing pending.

The patient lives on a North Dakota Native American reservation with her parents and siblings, with no sick contacts. She had no history of travel, and the only animal exposure was to healthy family dogs. Interestingly, about 2 weeks before the onset of her illness, a tornado had damaged the roof of the family home, exposing old insulation material.

What’s your diagnosis?

A. Sin Nombre virus

B. Hantavirus

C. Four Corners virus

D. Pseudomonas fluorescens

pneumonia

PAGE BREAK

Case Discussion

The answer can be A, B or C. The confirmatory Hantavirus IgM returned positive for the Sin Nombre virus, confirming the diagnosis of Hantavirus cardiopulmonary syndrome. There are more than 50 species of the genus Hantavirus, including Sin Nombre (or “no name”) virus, also known as Four Corners virus, the one responsible for most infections in the Four Corners area of the Southwest, where Colorado, New Mexico, Utah and Arizona come together. The deer mouse is the vector there. Other species of mice may carry different species of the Hantavirus in other areas of the country and world, but this region is where the disease was first recognized and studied when there was an outbreak in 1993. That year, the weather conditions favored a much larger than usual population of deer mice, thereby increasing the chance of spread. Hantavirus cardiopulmonary (HCP) syndrome usually results from inhaling the aerosolized urine or excrement containing the virus. In this case, the exposure likely came from aerosolized virus created by the tornado that swept through the area.

The incubation period is between 1 to 8 weeks, and the early clinical symptoms include flu-like complaints with fever. Within a week, the patient progresses into more severe respiratory distress with cardiogenic shock, requiring intensive care, where the mortality rate can still be up to 35%.

Day 14 of illness.

Although a small amount of Pseudomonas fluorescens was recovered from the BAL, this organism would not be the best explanation for the clinical picture of bilateral, diffuse lung disease with shock and DIC, with negative blood cultures, in a patient with community-acquired pneumonia with no indication of immune deficit or chronic lung disease. This most likely represented a small amount of contamination.

After 4 days on ECMO, the patient transitioned to a conventional ventilator for 2 more days and was then extubated. She rapidly improved, with resolution of all abnormal symptoms and findings, and she was discharged in good health on day 14 of her illness (Figure 4). This case represents the 14th confirmed case of HCP syndrome in North Dakota. A site investigation failed to find any rodents in the family home.

Disclosure: Brien reports no relevant financial disclosures.

I would like to thank Theresa Madigan, MD, pediatric infectious diseases fellow, Mayo Clinic, Rochester, Minnesota, for serving as guest contributor.