Achromobacter xylosoxidans Septic Arthritis in a Child with Primary Immunodeficiency.

Sir,

Achromobacter is a Gram-negative aerobic bacilli known to cause opportunistic infections in neonates and patients with HIV infection,[1] cancer,[2] cystic fibrosis,[3] and hyper-immunoglobulin M[4] syndrome. We report a case of Achromobacter xylosoxidans sepsis with septic arthritis in a child with suspected severe combined immunodeficiency (SCID).

A 2-year and 11-month-old male child presented with complaints of high-grade fever with swelling and restriction of movement of bilateral knee joints for 10 days. There was a history of multiple respiratory infections starting at 1 year of age, including an episode of empyema thoracis. Initial investigations revealed total leukocyte count 28,360 cells/mm3, neutrophil 65%, lymphocyte 25%, monocyte 7%, eosinophils 3% (absolute neutrophil count = 18,434/mm3 and absolute lymphocyte count = 7090/mm3), and C-reactive protein 290 mg/dl. Bilateral knee aspirates revealed acute inflammatory exudate. The child was empirically started on injection ceftriaxone and cloxacillin; however, there was no response in 72 h.

On day 4, his initial blood culture and knee aspirates showed growth of A. xylosoxidans. All the isolates were sensitive to ceftazidime, ciprofloxacin, and levofloxacin and resistant to gentamicin, amikacin, ceftriaxone, and cotrimoxazole. The antibiotic was changed to ceftazidime. Patient's joint symptoms improved and he became afebrile within 7 days of starting ceftazidime, which was continued for 6 weeks.

In view of a history of recurrent respiratory infection and disseminated infection with an opportunistic pathogen, possibility of immunodeficiency was considered. HIV serology was negative. His immune globulin profile showed severe panhypogammaglobulinemia and lymphocyte subset study was suggestive of T− NK− B+ SCID [Table 1]. Intravenous immunoglobulin was given as a replacement therapy for panhypogammaglobulinemia. The child was advised monthly intravenous immunoglobulin replacement therapy and cotrimoxazole prophylaxis. He was referred for genetic testing and stem cell transplant. Mother was advised carrier testing for genetic counseling to explain the risk in future pregnancy.

Table 1

Immunoglobulin Profile and Lymphocyte Subset Analysis of the Patient

A. xylosoxidans infections are more common in immunocompromised hosts with indwelling catheters, endotracheal tubes, or other medical devices. It may disseminate and cause sepsis, meningitis, and death. It is a very rare cause of septic arthritis. A. xylosoxidans is found in water sources, and well water is considered to be the source of community-acquired infections and intravenous fluid, ventilator, or dialysis fluid in nosocomial infection. It is usually multiresistant to antimicrobial therapy.

SCID is most severe form of primary immune deficiency with a presentation in early infancy with recurrent infections and failure to thrive. Atypical or milder expression of SCID with genetic defects known to be associated with classical disease is reported.[5] Maternal T-cell engraftment is considered as a possible explanation for such atypical presentation.

To conclude, A. xylosoxidans is an emerging opportunistic pathogen. Although recurrent infections are common in children in developing countries, diagnosis of primary immunodeficiency should be considered in presence of severe, unusual, prolonged, or recurrent infections.

Financial support and sponsorship

Nil.

Conflicts of interest

There are no conflicts of interest.