Pregnancy complicated by severe Chlamydia psittaci infection acquired from a goat flock: a case report

Tigecycline in the treatment of severe pneumonia caused by Chlamydia psittaci: A case report and literature review

Psittacosis is a zoonotic disease caused by Chlamydia psittaci. Systemic infections are mainly transmitted through the respiratory tract. The most common related disease is human atypical pneumonia, which is a rare pathogen of community-acquired pneumonia. Due to the difficulty of diagnosis, there have been few reports of C. psittaci pneumonia in the past. In recent years, with the widespread application of metagenomic next-generation sequencing (mNGS), the number of reported cases of C. psittaci has increased year by year. However, at present, most hospitals have little understanding of C. psittaci, especially for severe patients, and lack experience in diagnosis and treatment. Herein, we report the case of a 71-year-old woman with severe pneumonia that caused by C. psittaci. This patient was diagnosed through mNGS and was treated with tigecycline successfully. The level of IL-6 in the BALF was significantly increased. We discontinued tigecycline after mNGS of the blood was negative. In this review, we analyzed 53 cases to summarize the etiology, clinical manifestations, diagnosis and treatment strategies of severe C. psittaci pneumonia and hope to raise clinicians' awareness of this disease.

Gestational psittacosis: A case report and literature review

Gestational psittacosis is a rare disease that is associated with significant maternal and fetal morbidity and mortality. Currently, there is no examination method which allows for a quick diagnosis. We report a case of gestational psittacosis that could not be diagnosed as psittacosis during treatment and resulted in maternal and fetal death despite intensive treatment. We also reviewed 23 cases of gestational psittacosis. Fetal and maternal mortality was 82.6% (19/23) and 8.7% (2/23), respectively. In pregnant women with high fever and flu-like symptoms, we should suspect Chlamydia psittaci infection if at least one of the following is present; contact with sheep, parrots, parakeets or goats; normal or moderately decreased leucocyte count, thrombocytopenia and hepatic and/or renal dysfunction; cough and/or lobe consolidation or infiltration on chest X-ray. Antibiotic therapy with macrolide prenatally, macrolide or tetracycline postnatally and termination of pregnancy should be considered.

Zoonotic risks from small ruminants

Zoonoses are infections that spread naturally between species (sometimes by a vector) from animals to other animal species or to humans or from humans to animals. Most of the zoonoses diagnosed in sheep and goats are transmitted by close contact of man with these animals and are, more often, occupational diseases that principally affect breeders, veterinarians and/or slaughterhouse workers. Some other diseases have an airborne transmission and affect the population in the vicinity of sheep/goat farms. Due to the fact that small ruminants are almost the only remaining animals which are migrating in industrialised countries, there is a severe risk for transmitting the diseases. Some other zoonotic diseases are foodborne diseases, which are mainly transmitted from animals to humans and to other animal species by contaminated food and water. Within the last decade central Europe was threatened by some new infections, e.g., bluetongue disease and schmallenberg disease, which although not of zoonotic interest, are caused by pathogens transmitted by vectors. Causal agents of both diseases have found highly effective indigenous vectors. In the future, climate change may possibly modify conditions for the vectors and influence their distribution and competence. By this, other vector-borne zoonotic infections may propagate into former disease free countries. Changes in human behaviour in consummation and processing of food, in animal housing and management may also influence future risks for zoonosis. Monitoring, prevention and control measures are proposed to limit further epidemics and to enable the containment of outbreaks. Measures depend mainly on the damage evoked or anticipated by the disease, the local situation, and the epidemiology of the zoonoses, the presence of the infective agent in wild and other animals, as well as the resistance of the causal microorganisms in the environment and the possibility to breed sheep and goats which are resistant to specific infections. In this review, the clinical signs in animals and humans of the main sheep and goat zoonoses, as well as the transmission route and the control measures are reported. Brucellosis, chlamydophilosis, Q fever, Orf, Rift valley fever and Bovine Spongiform Encephalopathy are described in greater detail, in order to determine factors that contribute to the choice of the control strategies.

Zoonotic potential of Chlamydophila

The purpose of this article is to present the diseases induced in humans and animals by the different species of Chlamydophila, after providing an overview on the history of these infectious agents and their taxonomy. The route of transmission and the available methods for prevention and control in the different animal species are reviewed.

Emerging Chlamydial Infections

Chlamydiae are important intracellular bacterial pathogens of vertebrates. In the last years, novel members of this group have been discovered: Parachlamydia acanthamoebae and Simkania negevensis seems to be emerging respiratory human pathogens, while Waddlia chondrophila might be a new agent of bovine abortion. Various species have been showed to infect also the herpetofauna and fishes, and some novel chlamydiae are endosymbionts of arthropods. In addition, molecular studies evidenced a huge diversity of chlamydiae from both environmental and clinical samples, most of such a diversity could be formed by novel lineages of chlamydiae. Experimental studies showed that free-living amoebae may support multiplication of various chlamydiae, then could play an important role as reservoir/vector of chlamydial infections. Here we reviewed literature data concerning chlamydial infections, with a particular emphasis on the novely described chlamydial organisms.

Veterinary and medical aspects of abortion in Danish sheep

The Danish sheep population totals around 144,000 animals, but little is known of the causes and prevalance of diseases. This study focuses on the causes of abortion in Danish sheep. During one breeding season, aborted foetuses and stillbirths with signs of intrauterine death or malformation were submitted for laboratory examination from a population of 3,758 breeding ewes. Samples from 24 incidents of abortion and 21 ewes delivering malformed lambs or lambs with ante partum decomposition were submitted. A specific aetiology was established in 66.7% and 14.3% of the cases, respectively. Bacterial pathogens were the most prevalent cause of abortion. Several of the abortifacients were zoonotic microorganisms, for example Listeria monocytogenes, Campylobacter fetus subsp. fetus, Yersinia pseudotuberculosis and Toxoplasma gondii. The identified microorganisms probably represent the most common causes of abortion in Danish sheep but occurrence in Denmark of other pathogens such as Coxiella burnetii and Chlamydophila abortus cannot be excluded. Due to the high prevalence of zoonotic microorganisms, precautions must be taken in handling abortions or assisting lambing, especially for pregnant women.

Serological diagnosis of ovine enzootic abortion by enzyme-linked immunosorbent assay with a recombinant protein fragment of the polymorphic outer membrane protein POMP90 of Chlamydophila abortus

Ovine enzootic abortion (OEA) resulting from infection of sheep and goats with Chlamydophila abortus is of major economic importance worldwide. Over the last 50 years the serological diagnosis of infection has been based mainly on the complement fixation test (CFT), which lacks both sensitivity and specificity because of cross-reactive antibodies to other gram-negative bacteria, including another common chlamydial pathogen of sheep, Chlamydophila pecorum. In the present study, a series of overlapping recombinant antigens representing the polymorphic outer membrane protein POMP90 of C. abortus was assessed by enzyme-linked immunosorbent assay (ELISA) with a panel of 143 serum samples from sheep experimentally infected with C. abortus, from sheep clinically free of OEA, and from specific-pathogen-free lambs experimentally infected with different subtypes of C. pecorum. The results were compared to those obtained by CFT and another recently described test, an indirect ELISA (iELISA) with the recombinant OMP91B (rOMP91B) fragment (rOMP91B iELISA) (D. Longbottom, E. Psarrou, M. Livingstone, and E. Vretou, FEMS Microbiol. Lett. 195:157-161, 2001). The rOMP90-3 and rOMP90-4 ELISAs were identified as being more sensitive and specific than CFT. Assays with both fragments were evaluated further with a panel of 294 field serum samples from flocks with documented histories of abortion, from flocks with no clinical histories of abortion but which had a high proportion of samples seropositive by CFT, and from animals with no histories of abortion but from which various C. pecorum subtypes had been isolated. ELISAs with both POMP90 fragments outperformed CFT with serum samples from C. pecorum-infected animals, producing no false-positive results. However, the ELISA with the rOMP90-4 fragment appeared to be more sensitive than the one with rOMP90-3, as it identified more of the OEA-positive samples. The ELISA with the rOMP90-4 fragment was also able to identify apparently healthy animals that were infected with an enteric strain of C. abortus in flocks that were probably infected with both enteric C. abortus and C. pecorum strains. The identification of animals infected with enteric C. abortus is extremely important in controlling the spread of OEA. Overall, the new rOMP90-4 ELISA was found to be a more sensitive and specific test than CFT for differentiating animals infected with C. abortus from those infected with C. pecorum.

Gestational psittacosis in a Montana sheep rancher

In humans, psittacosis is primarily a flulike illness following exposure to psittacine birds. In rare cases, pregnant women exposed to Chlamydia psittaci can contract gestational psittacosis: atypical pneumonia, sepsis, and placental insufficiency resulting in premature birth or miscarriage. In the United States, only two cases of gestational psittacosis have been reported, both from exposure to psittacine birds. Eleven other cases have been reported worldwide, mostly in the United Kingdom, all from exposure to infected birth fluids and membranes of farm mammals, notably sheep and goats. In these mammals, C. psittaci inhabit the reproductive tract, are transmitted sexually or by the fecal-oral route, and cause miscarriages. The case of gestational psittacosis in a Montana sheep rancher is the first farm animal-related case reported in the United States. Pregnant women should avoid close contact with C. psittaci-infected animals, particularly sheep and goats during the birthing season. Obstetricians should consider this diagnosis along with early antibiotic treatment and cesarean section delivery in the context of the patient's case history.

Severe psittacosis during pregnancy and suppression of antibody response with early therapy

A cluster of 3 cases of psittacosis occurred among members of one family. The initial case was a pregnant woman who presented with extensive multilobar infiltrates and severe respiratory distress necessitating mechanical ventilation. Her respiratory failure worsened during 36 h of erythromycin therapy. Improvement coincided with the termination of pregnancy and the initiation of doxycycline treatment. The remaining patients developed milder illness. Serologic assessment of the affected subjects suggests that early treatment may suppress antibody response.