Nocardia paucivorans – A cause of disseminated Nocardiosis

Fatal Nocardia paucivorans Lower Respiratory Tract Infection in a Tuberculosis Suspect Who Worked as Gold Miner

Nocardiosis is an opportunistic infection that affects both immunocompromised as well as immunocompetent patients. The main infections occur as soft tissue and lung infections although they might disseminate to various organs. This is a case study aimed to reflect the severity of the disease and the patient's risk factors associated with the infection. A sputum sample was collected from tuberculosis (TB) suspects for culture. Nocardia-like colonies were isolated, purified, and sent to BGI Company (Hongkong, China). Standard forward sequencing of 16S rRNA was done by ABI Genetic Analyzer (Applied Biosystems). Sequence alignment and nucleotide basic local alignment search tool (BLAST) were done using National Center for Bioinformatics (NCBI) Nucleotide BLAST. Biochemical identification to the colonies was done using an automation system (BD Phoenix™) to confirm the identification. Nocardia paucivorans was identified from the TB suspect. Risk factors were identified as extensive contact to dust, absence of primary care units with complete facilities, and old age. Since the infection of the lungs caused by Nocardia might be similar to pulmonary TB, this case report highlights the importance of accurate diagnosis and identification procedures to differentiate between the two.

Disseminated Nocardiosis Masquerading as Soft-Tissue Malignancy: A Case Report

CASE

A 59-year-old man, immunosuppressed after renal transplant, presented with a painful posterior thigh mass concerning for malignancy, as well as pulmonary and posterior chest wall nodules. Cultures and mass spectrometry identified Nocardia paucivorans. The patient underwent operative irrigation and debridement of the posterior thigh and chest wall, with 12 months of antibiotic therapy.

CONCLUSION

A 2-week delay in appropriate treatment was due to low suspicion for infectious etiology. Since cultures generally take weeks for positive diagnosis, advanced molecular or biochemical methods should be used. This case demonstrates importance in maintaining a high index of suspicion for nocardiosis in immunocompromised patients with soft-tissue masses.

Successful treatment of peritoneal nocardiosis caused by Nocardia paucivorans in a dog

CASE HISTORY

A 7-year-old neutered female Labrador Retriever from Hesse (Germany) was referred for evaluation of peritoneal nodular masses identified by the referring veterinarian during an investigation for a 2-month history of lethargy.

CLINICAL FINDINGS AND TREATMENT

Ultrasonographic examination of the abdomen showed multiple cavernous nodules in the intra-abdominal fat and greater omentum surrounded by free fluid. These findings were suspicious of steatitis and fatty tissue necrosis in the cranial abdomen. Cytologic and microbiological analysis of fine-needle aspirates of the fatty tissue and abdominal fluid revealed septic pyogranulomatous inflammation caused by Nocardia paucivorans. The septic abdomen indicated surgical management was appropriate and a celiotomy was performed, which revealed an inflammed mass attached by fibrous tissue to the spleen, stomach and liver. All abnormal tissue including parts of the greater omentum and the spleen, were removed and samples taken for histopathology and microbial culture. Following surgery, the dog was treated with amoxicillin/clavulanic acid. After initially improving, the dog's condition deteriorated 3 months later. Based on ultrasonographic and cytologic findings, and bacterial culture, recurrence of peritoneal nocardiosis was confirmed. In a second celiotomy, multiple inflammatory mass lesions inflammed masses in the remaining greater omentum were removed. After surgery, antimicrobial therapy was changed to trimethoprim/sulfamethoxazole for a 10-month period. No recurrence of clinical signs was reported 6, 12 and 27 months after the initial surgery.

DIAGNOSIS

Peritonitis caused by Nocardia paucivorans.

CLINICAL RELEVANCE

To our knowledge, this is the first published report of canine infection with Nocardia paucivorans and the first case of peritoneal nocardiosis successfully treated in a dog. This report indicates that reducing the microbial burden by surgical debridement of affected tissues and peritoneal lavage followed by long-term treatment with a suitable antimicrobial may be an effective treatment for peritoneal nocardiosis in dogs.

Rare nocardiosis in danish patient with diabetes

We herein report a rare case that describes and visualizes nocardiosis in a patient with diabetes. The patient presented with recurring fever, gout, leg pain, frailty and muscular pain through nine months, before a core needle biopsi, from an abscess in the abdominal musculature, revealed Nocardia Paucivorans. A PET-CT-scan showed multiple muscular FDG-positive sites. Furthermore, he experienced serious side effects to Sulfametoxazole and Trimethoprim, the antibiotic of choice for this type of infection. He was then switched to Moxifloxacin and Ampicillin. Nocardia often presents as opportunistic infections, typically in patients with severe immunodeficiencies, such as HIV, use of high-dose corticosteroids, hematologic malignancies or immunosuppression following organ transplantation. This case illustrates how a patient with only relative immunodeficiency gets rare nocardiosis. Our sparse knowledge on clinical presentation is based on case-reports and treatment is empirical. Hence, a better understanding of the clinical presentation and treatment is important. Especially given the prospect, that the health care system faces a greater load of patients with diabetes and other immunodeficiencies in the future.

Intra-Abdominal Nocardiosis-Case Report and Review of the Literature

Nocardiosis is primarily an opportunistic infection affecting immunosuppressed individuals, in whom it most commonly presents as pulmonary infection and sometimes cerebral abscesses. Isolated abdominal or retroperitoneal nocardiosis is rare. Here, we report the second case, to our knowledge, of isolated abdominal nocardiosis due to Nocardia paucivorans and provide a comprehensive review of intra-abdominal nocardiosis. The acquisition of abdominal nocardiosis is believed to occur via hematogenous spreading after pulmonary or percutaneous inoculation or possibly via direct abdominal inoculation. Cases of Nocardia peritonitis have been reported in patients on peritoneal dialysis. Accurate diagnosis of abdominal nocardiosis requires histological and/or microbiological examination of appropriate, radiologically or surgically obtained biopsy specimens. Malignancy may initially be suspected when the patient presents with an abdominal mass. Successful therapy usually includes either percutaneous or surgical abscess drainage plus prolonged combination antimicrobial therapy.

Nocardia paucivorans brain abscess. Clinical and microbiological characteristics

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Brain abscess caused by Nocardia paucivorans is an infrequent infection in humans.

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Molecular speciation has revolutionized the study of Nocardia spp. infections.

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N. paucivorans brain abscess has a favourable prognosis with long-term antimicrobial therapy.

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Antimcirobial susceptibility testing is a useful guide to therapy.

Nocardia paucivorans brain abscesses are unusual in humans. Sixteen cases of this infection have been reported in the world medical literature. There is precise clinical information available from nine patients. All of these patients recovered or were cured from their brain disease with long-term antimicrobial treatment. Surgical drainage was performed in four patients.

Brain Abscesses Caused by Nocardia paucivorans in a Multiple Myeloma Patient Treated with Lenalidomide and Dexamethasone: a Case Report and Review of Literature

We report the first case of multiple brain abscesses caused by Nocardia paucivorans in a patient suffering from multiple myeloma on treatment with lenalidomide and dexamethasone. N. paucivorans is a recently described species of the genus Nocardia, which is supposed to have a heightened neurotropism in cases of disseminated infection. Although nocardiosis itself is an uncommon infectious complication in multiple myeloma so far, nocardial brain abscess should be added to the spectrum of adverse effects due to this novel chemotherapy regimen.

[Different manifestations of the cerebral nocardiosis]

Nocardial infections affect mainly the respiratory tract but also can attack the CNS. Clinical experience with cerebral nocardiosis is very limited. We present two patients with very different cerebral affections due to nocardiosis. Cerebral nocardial infections can cause both multiple small abscesses and single large abscesses in the human brain. Despite the rare incidence of cerebral nocardiosis, it is an important differential diagnosis of expansive processes and abscesses in the CNS.

[Pulmonary nocardiosis in a patient who was a chronic corticosteroid user]

Pulmonary nocardiosis is an infrequent and severe infection caused by Nocardia spp. These are microorganisms that may behave both as opportunists and as primary pathogens, and they may present as either acute or suppurative chronic disorders. We report on the case of a 49-year-old man with idiopathic thrombocytopenic purpura that was being treated with corticosteroids. He developed pulmonary infection due to Nocardia farcinica, which was isolated from blood cultures. Despite correct treatment with trimethoprim-sulfamethoxazole, the patient died three months after this therapy was instituted.