Medical Image of the Week: Ascaris Lumbricoides

Figure 1. 23 cm adult Ascaris lumbricodes recovered from patient's feces.

A 25 year-old man was admitted to the ICU with acute renal failure and acute respiratory failure from fluid overload after attempting to cross the border. The patient was successfully extubated after five days of mechanical ventilation and renal replacement therapy. Following extubation, the patient had a bowel movement and passed a 23cm adult Ascaris lumbricoides. He was treated with a single dose of albendazole 400 mg.

Ascariasis is a very common helminthic infection, particularly in pediatric populations, and affects mostly the gastrointestinal tract. When infective eggs are swallowed by the host, larvae hatch in the GI tract. The larvae invade the GI mucosa and then are brought into the lungs via portal circulation. The larvae can then move up the tracheobronchial tree and then are swallowed into the GI tract where the mature worms form (1).

While our patient had a simple gastrointestinal infection, several pulmonary complications of ascariasis have been reported (2). Adult worms can cause largyngospasm as well as mechanical obstruction of the airway which can result in cardiac arrest (3,4). This migration of worms from the stomach to the trachea may be related to the use of anesthetics and the subsequent relaxation of the lower esophageal sphincter. Ascaris larvae have been implicated in Loeffler’s syndrome, also described as simple pulmonary eosinophilia, characterized by transient pulmonary infiltrates and eosinophilia with a usually benign course.

Candy Wong¹; Aaron Fernandes², Jennifer Huang², and Sachin Chaudhary¹

¹Division of Pulmonary, Critical Care, Allergy, and Sleep Medicine.

² Department of Medicine

University of Arizona

Tucson, AZ

References

1. Centers for Disease Control and Prevention. Parasites – Ascariasis. Biology. Available at: http://www.cdc.gov/parasites/ascariasis/biology.html (accessed 1/13/2015).
2. Li QY, Zhao DH, Qu HY, Zhou CN. Life-threatening complications of ascariasis in trauma patients: a review of the literature. World J Emerg Med. 2014;5(3):165-70. [CrossRef] [PubMed]
3. Maletin M, Veselinović I, Stojiljkovic GB, Vapa D, Budakov B. Death due to an unrecognized ascariasis infestation: two medicolegal autopsy cases. Am J Forensic Med Pathol. 2009;30(3):292-4. [CrossRef] [PubMed]
4. Husain SJ, Zubairi AB, Sultan N, Beg MA, Mehraj V. Recurrent episodes of upper airway blockage associated with Ascaris lumbricoides causing cardiopulmonary arrest in a young patient. BMJ Case Rep. 2009;2009. pii: bcr01.2009.1415. [CrossRef] [PubMed]

Reference as: Wong C, Fernandes A, Huang J, Chaudhary S. Medical image of the week: ascaris lumbridoies. Souhtwest J Pulm Crit Care. 2015;10(2):81-2. doi: http://dx.doi.org/10.13175/swjpcc008-15 PDF

Medical Image of the Week: Wide Mediastinum Due to Lung Infiltrates

Figure 1. Panel A: Admission chest x-ray showing an apparent widened mediastinum. Panels B & C: CT scan showing consolidation in the posterior lungs bilaterally. Panel D: Chest x-ray showing resolution of his widened mediastinum with an increase in positive end-expiratory pressure.

The patient is a 65-year-old man patient with a past medical history of poorly controlled hypertension and coronary artery disease who was admitted after a witnessed code arrest. He was found down, and paramedics arrived within 5 minutes and started chest compressions. His initial CXR showed a wide mediastinum (Figure 1A) that was concerning for possible aortic dissection especially with his history of poorly controlled hypertension. Due to his hemodynamic instability a chest CT scan couldn’t be done initially, but the patient underwent a trans-esophageal echo that was negative for aortic dissection.

When the patient became more stable a chest CT scan with contrast was done and showed consolidation of the medial parts of both lungs with 7 bilateral rib fractures (Figure 1 B & C). The impression was either lung contusion from the aggressive chest compression as evidenced by the bilateral 7 rib fractures or aspiration in the dependent parts of the lung. His apparent widened mediastinum resolved with increasing the positive end-expiratory pressure (PEEP) on the ventilator within 48 hours (Figure 1D).

Huthayfa Ateeli MBBS, Laila Abu Zaid MD

Department of Medicine

University of Arizona

Tucson, AZ.

References

1. Cohn SM. Pulmonary contusion: review of the clinical entity. J Trauma. 1997;42(5):973-9. [CrossRef] [PubMed]
2. Lai CC, Wang CY, Lin HI, Wang JY. Pulmonary contusion associated with chest compressions. Resuscitation. 2010;81(1):133. [CrossRef] [PubMed]

Reference as: Ateeli H, Zaid LA. Medical image of the week: widen mediastinum due to lung infiltrates. Southwest J Pulm Crit Care. 2015;10(2):77-8. doi: http://dx.doi.org/10.13175/swjpcc007-15 PDF