Evidence: Pet bird (psittacine) clinical cases
Source: Europe PMC (Europe PubMed Central) REST search — first-hand peer-reviewed abstract records, pulled 2026-08-01. Queries covered clinical case reports and case series for psittacine. The cluster returns 12 representative clinical cases with abstracts below. Abstract text is verbatim from source; each case is traceable by PMID.
Studies
- PMID 42338934 (2026, Frontiers in medicine) — A case report of spherical pneumonia caused by <i>Chlamydia psittaci</i> infection.. Abstract (opening): Psittacosis is a zoonotic infectious disease caused by <i>Chlamydia psittaci</i>, typically transmitted from birds to humans. Its clinical manifestations are often subtle and non-specific, making it prone to being misdiagnosed as common community-acquired pneumonia. Round pneumonia (or spherical pneumonia) refers to a lung infection that appears as a round or oval density on computed tomography (CT). It is uncommon in adults. Spherical pneumonia specifically caused by <i>Chlamydia psittaci</i> infection is particularly uncommon. Here we report a case of a 43-year-old male who was admitted due to a 4-day history of fever. CT imaging revealed a solitary, round high-density shadow approximately 4 cm in diameter in the right lower lung, with clear margins and surrounding ground-glass opacity. The patient reported direct contact with ornamental parrots at a zoo 10 days before the onset of symptoms. The diagnosis of spherical pneumonia caused by <i>Chlamydia psittaci</i> infection was confirmed by targeted next-generation sequencing (tNGS). The patient's symptoms resolved following treatment with minocycline, and a follow-up CT scan 32 days later showed near-complete resolution of the lesion. This case demonstrates that <i>Chlamydia psittaci</i> can also produce a typical spherical lesion, thereby broadening the recognized imaging spectrum of this pathogen. When clinicians encounter a patient with imaging findings suggestive of spherical pneumonia and a history of bird exposure, <i>Chlamydia psittaci</i> infection should be suspected, especially when accompanied by extrapulmonary symptoms such as headache, myalgia, or hepatosplenomegaly, necessitating a comprehensive assessment that integrates epidemiological history and molecular diagnostic methods.
Source: https://pubmed.ncbi.nlm.nih.gov/42338934/
- PMID 41810234 (2026, Frontiers in medicine) — <i>Cryptococcus neoformans</i> infection presenting as a mediastinal mass in an immunocompetent child with parrot exposure: a case report and literature review.. Abstract (opening): <i>Cryptococcus neoformans</i> typically causes pulmonary or central nervous system (CNS) infections, but mediastinal mass as its primary manifestation is rare-especially in immunocompetent children with pet parrot exposure. This study reports a 7-year-old girl who presented with recurrent fever and a mediastinal mass secondary to <i>Cryptococcus neoformans</i> infection, with a 5-month history of daily contact with parrot feces. Conventional diagnostic tests (e.g., fungal culture, serology) were negative, and the diagnosis was confirmed by targeted metagenomic next-generation sequencing (tNGS) of bronchoalveolar lavage fluid (BALF). The patient received a three-phase antifungal regimen: induction with amphotericin B + flucytosine, consolidation with fluconazole, and maintenance with low-dose fluconazole. After one year of treatment, the mediastinal mass nearly resolved, and no recurrence was observed. A literature review, supplemented with specific cases of parrot-associated <i>Cryptococcus neoformans</i> infection, highlights that parrot exposure is an underrecognized risk factor for pediatric cryptococcosis, and tNGS significantly improves diagnostic efficiency for atypical extrapulmonary manifestations. This case emphasizes the importance of inquiring about pet bird exposure in children with unexplained mediastinal masses and fever, and supports the use of tNGS for early, non-invasive diagnosis.
Source: https://pubmed.ncbi.nlm.nih.gov/41810234/
- PMID 41919237 (2026, Frontiers in pharmacology) — Successful azithromycin treatment of <i>Chlamydia</i> psittaci pneumonia in second-trimester pregnancy resulting in term delivery: a case report.. Abstract (opening): Psittacosis pneumonia is a zoonotic infection caused by <i>Chlamydia</i> psittaci (C. psittaci), primarily transmitted via contact with infected avian species. Diagnostic challenges arise from the inherent difficulties of pathogen culture and serological testing, frequently resulting in misdiagnosis or underdiagnosis. Gestational psittacosis, in particular, is a rare but life-threatening condition, with delayed diagnosis conferring risk of severe maternal and fetal complications. We present a case of C. psittaci pneumonia in a 24-week pregnant woman, with the diagnosis confirmed by metagenomic next-generation sequencing (mNGS). Empirical intravenous azithromycin (0.5 g daily) was promptly initiated for 3 days, leading to rapid symptomatic resolution. After a 2-day interruption, targeted oral azithromycin (0.5 g daily) was restarted for an additional 3 days following pathogen confirmation via mNGS. The patient was successfully discharged after a 10-day hospital stay under multidisciplinary management. She finally gave birth to a healthy baby girl at 40 weeks and 3 days of gestation, with favorable maternal and neonatal outcomes. To our knowledge, this represents one of the few reported cases of full-term delivery following azithromycin monotherapy for gestational psittacosis. It provides valuable insights into the diagnosis and management of gestational psittacosis, emphasising the importance of multidisciplinary involvement in preserving maternal and fetal safety.
Source: https://pubmed.ncbi.nlm.nih.gov/41919237/
- PMID 42255501 (2026, Science in One Health) — The re-emergence of psittacosis in China: a scoping review of epidemiology, diagnostics, and One Health priorities.. Abstract (opening): Psittacosis caused by <i>Chlamydia psittaci</i> has re-emerged in China as sporadic cases and localized outbreaks. However, current knowledge remains fragmented across the clinical, veterinary, epidemiological, and public health fields. This scoping review mapped studies on psittacosis in China, identified major knowledge gaps, and defined priorities for research, clinical management, and prevention and control. Following the Arksey and O'Malley framework and Preferred Reporting Items for Systematic Reviews and Meta-Analyses extension for Scoping Reviews (PRISMA-ScR), China National Knowledge Infrastructure (CNKI), Wanfang, PubMed, Web of Science, and Embase were searched for studies published between 1 January 1985 and 31 December 2025 and synthesized eligible studies with descriptive statistics and thematic analysis. A total of 424 studies were included. Research interest showed recent sharp increases and was concentrated in Eastern and Central China. Case reports and series dominated the literature, whereas analytic epidemiology, standardized surveillance, and high-resolution molecular studies remained limited. Reported cases were most often documented in middle-aged and older adults with avian exposure, including pet birds and poultry, and the reported occurrence showed a winter-spring pattern. Pneumonia was the predominant clinical presentation, and severe cases could progress to acute respiratory distress syndrome and multi-organ dysfunction. Metagenomic next-generation sequencing (mNGS) was the most frequently reported diagnostic method in recent studies, while PCR and serology remained important complementary tools. Overall, the literature is growing rapidly, but remains uneven in geographic coverage, study design, and integration across human, animal, and environmental sectors. These findings support broader One Health surveillance, stronger analytic and molecular epidemiology, and more standardized approaches to diagnosis, source investigation, and prevention in China.
Source: https://pubmed.ncbi.nlm.nih.gov/42255501/
- PMID 41783864 (2026, Cureus) — Pediatric Allergy to Poultry Meat: A Case of Egg-Bird Syndrome.. Abstract (opening): Poultry meat allergy is a rare condition that can present as a primary allergy or a secondary syndrome, such as the egg-bird syndrome. This syndrome involves primary sensitization to egg yolk (alpha-livetin (Gal d 5)) leading to cross-reactivity with poultry meat. We describe the case of a 12-year-old male patient who presented with a history of primary egg allergy and allergy to dog epithelium. He subsequently developed an allergy to poultry meat. Immunoallergological evaluation showed sensitization to egg yolk, chicken meat, and alpha-livetin (Gal d 5). Sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) immunoblotting confirmed immunoglobulin E (IgE) reactivity to alpha-livetin and avian muscle serum albumin, with no cross-reactivity to dog epithelium. This confirmed the diagnosis of egg-bird syndrome. Due to severe asthma and multiple food allergies impacting his quality of life, the patient was treated with omalizumab. This case highlights the clinical complexity of the egg-bird syndrome and the utility of molecular diagnostics in differentiating cross-reactivities. Omalizumab proved effective in managing the patient's polysensitization and asthma, improving quality of life.
Source: https://pubmed.ncbi.nlm.nih.gov/41783864/
- PMID 41922412 (2026, Scientific reports) — Prevalence of Pseudomonas aeruginosa in Australian wild birds, native wildlife, livestock and domestic animals.. Abstract (opening): The ESKAPE pathogen, Pseudomonas aeruginosa, poses a serious threat to medical, veterinary, and agricultural practices globally, and thus has been declared a “Priority Pathogen” by the World Health Organisation. Understanding P. aeruginosa prevalence in wild bird populations, livestock, and domestic animals is vital for evaluating potential infection reservoirs. In this study, we screened 1,669 DNA samples obtained between 2010 and 2023 from healthy and diseased wild birds (n = 1,101), domestic animals (n = 269), livestock (n = 133), kangaroos (n = 39), and koalas (n = 127) from Southeast Queensland, Australia, for both P. aeruginosa and overall bacterial load using an ecfX-16 S rRNA duplex real-time PCR assay. P. aeruginosa-positive samples were also screened for the two most common fluoroquinolone resistance genotypes, GyrA Thr83Ile and GyrA Asp87Asn. Overall, only 1.8% of samples from our large and diverse sample set tested positive for P. aeruginosa. Livestock samples showed the highest P. aeruginosa prevalence (4.5%, n = 6), driven primarily by horses (7.4%, n = 5), with wild birds (1.5%, n = 17), koalas (1.6%, n = 2), and domestic animals (1.9%, n = 5) having the next highest rates. In contrast, no P. aeruginosa positive samples were identified in cattle (n = 45) or kangaroos (n = 39). Nearly all positive wild bird samples originated from eye swabs (94%, n = 16). No additional correlation between swab site, health status, or admission cause was identified. No GyrA Asp87Asn variants were seen; however, the GyrA Thr83Ile variant was seen in 2/30 (6.6%) P. aeruginosa-positive samples, both of horse origin. This finding suggests the presence of a fluoroquinolone resistant subpopulation, however confirmation through phenotypic resistance profiling was unable to be performed. Our findings provide important insight into the epidemiology of P. aeruginosa in Australian wildlife and domestic animal populations from South-East Queensland. Further prevalence studies, particularly covering a broader geographical region, are warranted to better elucidate nationwide P. aeruginosa carriage, infection, and fluoroquinolone resistance rates.
Source: https://pubmed.ncbi.nlm.nih.gov/41922412/
- PMID 41859052 (2026, Infection and drug resistance) — Clinical Features of 186 Cases of <i>Chlamydia psittaci</i> Pneumonia: A Multicenter Study.. Abstract (opening): <h4>Purpose</h4><i>Chlamydia psittaci</i> pneumonia is an uncommon type of pneumonia characterized by non-specific clinical manifestations. Current knowledge regarding its clinical features is insufficient. Therefore, we aimed to elucidate its epidemiological profile, clinical characteristics, and distinctions between severe and non-severe cases.<h4>Patients and methods</h4>Clinical data of 186 patients diagnosed with <i>C. psittaci</i> pneumonia using next-generation sequencing (NGS) were systematically collected from seven hospitals in Guangdong Province, China, between January 2019 and June 2025. Epidemiological characteristics, clinical presentations, laboratory results, chest computed tomography (CT) features, bronchoscopy findings, and treatment outcomes were analyzed, with comparisons by disease severity.<h4>Results</h4>Of 186 patients (58.1% male, 50-74 years), 43.5% presented with severe disease, and 67.2% developed complications. Most cases occurred during autumn or winter (67.2%), and a history of bird or poultry exposure was reported in 68.3%. Prevalent clinical symptoms included fatigue (98.9%), high fever (90.3%), and headache (73.7%). Laboratory findings showed elevated serum levels of C-reactive protein, procalcitonin, fibrinogen, and D-dimer in most patients (over 90%). Additionally, over 70% had increased neutrophilia, alanine transaminase, aspartate transaminase, and lactate dehydrogenase levels, with reduced lymphocyte counts. Chest CT findings frequently revealed pulmonary consolidation (100%), ground-glass opacities (97.8%), and air bronchograms (81.2%). Severe cases showed extensive bilateral and multilobar consolidation, with increased prevalence of pleural and pericardial effusions. The median time from admission to diagnosis was 3 (2-4) days, with 96.2% of patients improving following targeted antimicrobial therapy and being discharged, while 3.2% died.<h4>Conclusion</h4><i>C. psittaci</i> pneumonia is characterized by a high incidence of severe cases and both intrapulmonary and extrapulmonary complications. Its clinical manifestations are diverse and multifaceted, with hallmark features including high fever, relative bradycardia, normal white blood cell counts, elevated transaminases, and pulmonary consolidation. Early diagnosis through NGS and targeted antimicrobial therapy are associated with positive patient outcomes.
Source: https://pubmed.ncbi.nlm.nih.gov/41859052/
- PMID 40995776 (2026, Veterinary pathology) — Granulomatous arteritis/aortitis associated with <i>Mycobacterium genavense</i> in a colony of zebra finches (<i>Taeniopygia guttata</i>).. Abstract (opening): <i>Mycobacterium genavense</i> is a common cause of mycobacteriosis in passerine birds. In a research colony of zebra finches (<i>Taeniopygia guttata</i>), 8 birds were diagnosed with mycobacteriosis. The finches had granulomatous inflammation of the heart and heart-base, most with medial expansion of the great vessels containing foamy macrophages and acid-fast bacilli. Non-cardiac inflammatory lesions associated with acid-fast bacteria were found in 2 birds, and extracardiac bacteria were often in lower quantities. Pan-mycobacterial <i>in situ</i> hybridization detected periaortic bacteria in one bird with similar cardiac lesions that was negative for bacteria via acid-fast staining. <i>Mycobacterium</i> genus PCR and sequencing of pooled fecal samples confirmed the presence of <i>M. genavense</i> within the colony. Heart and great vessel lesions have not been previously recognized as a site of localized infection in passerines. To facilitate diagnosis of mycobacteriosis in zebra finches, routine necropsies should include microscopic examination of the heart base great vessels.
Source: https://pubmed.ncbi.nlm.nih.gov/40995776/
- PMID 42192709 (2026, Antibiotics (Basel, Switzerland)) — Pet Birds as Potential Reservoirs of Antimicrobial-Resistant Bacteria in Digestive and Respiratory Infections.. Abstract (opening): <h4>Background/objectives</h4>Pet birds are increasingly recognized as potential reservoirs of zoonotic and antimicrobial-resistant bacteria, raising concerns within the One Health framework. However, data on bacterial diversity and resistance profiles in clinically affected ornamental birds remain limited.<h4>Methods</h4>This study, conducted over three years (November 2022-March 2026), included 198 pet birds presenting with digestive and respiratory disorders. From these birds, clinical samples were analyzed bacteriologically; resulting isolates were identified by MALDI-TOF mass spectrometry, and antimicrobial susceptibility assessed using the Kirby-Bauer disk diffusion method according to EUCAST and CLSI guidelines.<h4>Results</h4>Bacterial growth was detected in 87.9% of cases, yielding 249 distinct isolates. Gram-positive cocci predominated (62.3%), led by <i>Staphylococcus</i> spp. (33.3%) and <i>Enterococcus</i> spp. (9.6%), while <i>Escherichia coli</i> (9.2%) was the primary Gram-negative species. At the genus level, <i>Staphylococcus</i> spp. demonstrated high susceptibility to amikacin (88.5%) but significant resistance to gentamicin (75.6%) and oxytetracycline (63.6%). In contrast, <i>Escherichia</i> spp. isolates were largely resistant, showing only 50% susceptibility to enrofloxacin and 40% to doxycycline, with resistance to tylosin reaching 90%. Overall, 57% of isolates were multidrug-resistant, with <i>Staphylococcus</i> spp. contributing most to this burden.<h4>Conclusions</h4>These findings characterize clinically ill pet birds as significant carriers of multidrug-resistant bacteria, highlighting the need for routine diagnostics and improved antimicrobial stewardship in avian medicine.
Source: https://pubmed.ncbi.nlm.nih.gov/42192709/
- PMID 41766230 (2026, The American journal of case reports) — Late-Onset Adenovirus-Induced Achalasia in a Kidney Transplant Recipient: A Case Report.. Abstract (opening): BACKGROUND Adenovirus infection in kidney transplant recipients, although rare, represents a potentially life-threatening complication that typically manifests early after transplantation. Late-onset adenovirus infection is uncommon and presents substantial diagnostic and therapeutic challenges, particularly in cases of atypical organ involvement. Esophageal involvement is exceptionally rare and has not been extensively characterized in solid-organ transplant recipients. CASE REPORT A 60-year-old male kidney transplant recipient presented with a 1-week history of dysuria, gross hematuria, diarrhea, and worsening graft function 5 years after transplantation. Progressive dysphagia developed after admission. Laboratory testing confirmed adenovirus infection in the blood, with a viral load of 779 000 IU/mL. Adenovirus was also detected in urine and stool samples, whereas cytomegalovirus and polyomavirus testing yielded negative results. Gastroscopy and barium swallow studies demonstrated achalasia-like features. Esophageal biopsy specimens did not show viral cytopathic changes. Management consisted of immunosuppression reduction, intravenous immunoglobulin administration, and low-dose cidofovir therapy. Clinical and virologic recovery was achieved within 3 weeks, with complete resolution of gastrointestinal symptoms and stabilization of graft function. CONCLUSIONS This case underscores the atypical late presentation of adenovirus infection in a kidney transplant recipient and illustrates the potential for extremely rare esophageal involvement manifesting as achalasia. Despite the absence of direct viral confirmation in esophageal tissue, the clinical course and therapeutic response support adenovirus as the most likely etiology. Early recognition, confirmation by polymerase chain reaction testing, and timely immunosuppression adjustment combined with antiviral therapy are essential to optimize patient outcomes.
Source: https://pubmed.ncbi.nlm.nih.gov/41766230/
- PMID 41727454 (2026, Frontiers in immunology) — Migratory vasodilatation of cerebral arteries in MELAS episodes: a case report and literature review.. Abstract (opening): Mitochondrial encephalomyopathy with lactic acidosis and stroke-like episodes (MELAS) is the commonest inherited mitochondrial disorder. Dilation of the major cerebral arteries is seldom mentioned in MELAS because magnetic resonance angiography (MRA) usually shows normal findings. Here, we described a 24-year-old male patient with MELAS who had migratory vasodilatation of cerebral arteries on MRA and positive antibodies against contactin-associated protein-like-2 in serum during stroke-like episodes (SLEs). Moreover, a total of 18 MELAS cases were included in this literature review. MELAS with cerebrovascular dilatation was mainly seen in young adults and the commonest clinical manifestations were visual symptoms, headache, and seizures. Vasodilatation predominantly occurred in the acute phase of SLEs. Dilation of the major cerebral artery mainly happened in the posterior cerebral artery and the middle cerebral artery. The region of increased cerebral blood flow (CBF) always corresponded to the range of vascular supply of the dilated cerebral artery. Multimodal neuroimaging evaluation is very important for the diagnosis of mitochondrial diseases. Migratory vasodilation of cerebral arteries may be a specific imaging sign of MELAS. Dilation of cerebral artery together with increased CBF not only indicates the clinical onset, but also implies an upcoming stroke-like attack.
Source: https://pubmed.ncbi.nlm.nih.gov/41727454/
- PMID 41640945 (2025, Frontiers in veterinary science) — Zoonotic potential of <i>Chlamydia psittaci</i>-a case report.. Abstract (opening): The causative agent of chlamydiosis/psittacosis, the obligatory intracellular bacterium <i>C. psittaci</i>, infects various species of birds and humans. Infected birds occasionally excrete the pathogen through the respiratory and digestive systems, with nasal/ocular discharge and feces being the main sources of infection for other birds or humans. Humans are most often infected through close contact with positive parrots. In this case report of avian chlamydiosis/psittacosis, samples were taken from a dead cockatiel and two budgerigars, and from a child living in the same household as the birds. In all the samples examined, except the child's serum, <i>C. psittaci</i> was detected by real-time PCR. The phylogenetic analysis of the <i>ompA</i> gene from parrot isolates identified genotype A, confirming that parrots harbored the most virulent genotype of <i>C. psittaci</i>. To prevent the spread of avian chlamydiosis/psittacosis, it is necessary to procure birds from verified sources, monitor the signs of disease in parrots and humans, and strictly adhere to biosecurity measures to prevent further spread of the disease.
Source: https://pubmed.ncbi.nlm.nih.gov/41640945/
Source text: pdf-raw/evidence/europepmc_pet_bird_clinical_2026-08-01.txt (Europe PMC first-hand abstracts, pulled 2026-08-01).