Case report details rare recurrent hemoptysis syndrome in a dog: full analysis

A newly published case report in Animals details the successful management of a male castrated Shih Tzu with recurrent nighttime episodes of acute respiratory distress, hemoptysis, and transient erythrocytosis, a combination the authors present as unusual in dogs. According to the report, the dog was clinically normal between episodes, but each crisis was abrupt, severe, and serious enough to prompt repeated emergency visits. The authors concluded that, after excluding more common causes, dysregulated sympathetic activity with splenic contraction was the most plausible mechanism, and they reported successful control with targeted therapy. The article was published April 30, 2026. (mdpi.com)

The background matters here because hemoptysis in dogs is relatively uncommon and usually points clinicians toward a different list of differentials. In a retrospective study of 36 canine cases cited in the paper, the most commonly reported causes were bacterial bronchopneumonia, respiratory neoplasia, and trauma, followed by systemic causes including heartworm disease and immune-mediated thrombocytopenia. That makes this Shih Tzu’s presentation notable: not just for the bleeding and respiratory distress, but for the repeatable, reversible rise in packed cell volume during acute episodes and the apparent return to normal between them. (mdpi.com)

According to the case report, thoracic radiographs obtained during emergency presentations showed severe diffuse interstitial-to-alveolar pulmonary infiltrates, while PCV and inflammatory markers improved rapidly over several days with supportive care, including oxygen therapy and antimicrobials. The authors said a sequential diagnostic and therapeutic approach failed to prevent recurrence until they considered a mechanism involving abnormal sympathetic activation and splenic contraction, which they linked to the transient erythrocytosis. Their report frames the condition as a form of recurrent noncardiogenic pulmonary edema with hemoptysis, rather than a more typical infectious, neoplastic, or cardiogenic process. (mdpi.com)

Outside this report, the broader literature offers some support for the authors’ reasoning, even if direct parallels appear limited. Veterinary references note that noncardiogenic pulmonary edema in dogs can be associated with airway obstruction, neurogenic causes, drug reactions, electrocution, drowning, transfusion-related injury, and other acute insults. Separate reports have also described recurrent paroxysmal respiratory distress with severe pulmonary infiltrates in dogs under specific circumstances, suggesting that episodic pulmonary injury syndromes may be underrecognized, even when the exact trigger differs. (mdpi.com)

I didn’t find substantial outside expert commentary or industry reaction to this specific paper yet, which isn’t surprising given how recently it was published. Still, one clinically relevant point is that prazosin has precedent in veterinary literature as an alpha-adrenergic blocker used in dogs with severe pulmonary vascular disease, even though that context is different from this case. That doesn’t validate the mechanism on its own, but it does make the authors’ therapeutic logic more intelligible for clinicians weighing whether sympathetic tone could be contributing to similar presentations. (dvm360.com)

Why it matters: For veterinarians, the report is less about establishing a new syndrome than about widening the diagnostic lens. Dogs that present with nocturnal, episodic respiratory distress and hemoptysis, then normalize between visits, can be difficult to categorize quickly in emergency practice. This case suggests that transient polycythemia may be reactive and reversible rather than primary, and that diffuse pulmonary infiltrates should not automatically be read as cardiogenic edema or pneumonia without considering timing, recurrence pattern, and the full workup. It also underscores the value of serial PCV assessment and repeat imaging in patients whose abnormalities may be dramatic but short-lived. (mdpi.com)

The case may also resonate with practices that see brachycephalic or small-breed dogs with poorly explained overnight respiratory crises. While this is only a single case report, it raises the possibility that autonomic dysregulation, pulmonary vascular shifts, or splenic contraction could play a role in select patients whose workups are otherwise unrewarding. For pet parents, that may eventually translate into more tailored counseling around recurrence risk and emergency planning, but the evidence base is still very early. (mdpi.com)

What to watch: The next question is whether additional reports, case series, or referral-center experience confirm this pattern and clarify which dogs might benefit from similar management. Until then, this publication is best viewed as an intriguing, hypothesis-generating case that may help clinicians think more broadly when recurrent hemoptysis and respiratory distress don’t fit the usual script. (mdpi.com)