Three siblings present with abscesses over 10 days
What’s your diagnosis?
Over a period of 3 weeks, just after the end-of-the-year holidays, three healthy siblings presented with swollen lymph nodes.
The first was a 6-year-old girl who presented with an abscess of a lymph node inferior to her right ear, shown in Figure 1. A needle aspiration was done yielding 2 mL of pus and relief of pain. Several days later, her 8-year-old brother presented with a history of a small scratch of the right forearm with subsequent development of a swollen epitrochlear node with abscess, shown in Figure 2. This node also underwent needle aspiration. Lastly, their 12-year-old brother presented 10 days later with an inflamed papular lesion on the lower abdomen, shown in Figure 3, and a painful, swollen right inguinal lymph node (not shown) that spontaneously drained the day before the visit, subsequently developing a draining fistula.
Figure 1 . A 6-year-old girl with an inflamed and swollen parotid lymph node. Courtesy of Michael Cater, MD. 
Figure 2 . The 8-year-old brother of the girl in Figure 1. Courtesy of Michael Cater, MD. 
Figure 3 . The 12-year-old brother of those in Figures 1 and 2 with inflamed papular lesion on lower abdomen. Courtesy of Michael Cater, MD. The family history is otherwise unremarkable. There was no preceding travel, or significant injuries to the areas of concern. As it is in the wintertime, there has been no insect exposure, such as mosquitoes or ticks. Their animal exposure is limited to a family dog and a cat, both of which are healthy and immunized. The cat had given birth to eight kittens 4 months earlier, which they still have.
What’s Your Diagnosis?
A. Bartonella henselae
B. Mycobacterium lepraemurium
C. Staphylococcus aureus
D. Toxoplasma gondii
Answer and discussion
The answer is A. All three children turned out to have common cat scratch disease (CSD), caused by Bartonella henselae; two cases were supported by serology and one by PCR of aspirated pus. With a compatible history in the appropriate clinical setting, these tests can help confirm the diagnosis. However, the possibilities of false-positive and false-negative results can be misleading, and oftentimes are not used if the historical and physical findings are classic.
The history of prolonged, close household exposure to kittens and subsequent development of similar clinical findings of subacute regional lymphadenitis with or without suppuration AND association of skin scratches (or less commonly, bites) with a typical cutaneous granuloma or papular lesion at the scratch site, make CSD a near certainty. As in these three cases, CSD is more likely to be transmitted by kittens in the winter months, but it can be seen year round.
Although it has been previously reported, it is unusual to see reports of simultaneous CSD in multiple members of a family in the same time frame. I suspect it happens periodically but just is not reported. Although one kitten can infect multiple people, in this case, it is likely that multiple kittens were infected around the same time by the bite of infected fleas.
After biting a bacteremic cat, the organism (Bartonella henselae) will be shed in their feces near the site of the flea bite. Then the cat responds by scratching or biting the area, contaminating their claws or mouth with the organism, which can then be easily transmitted by scratching the skin of the patient. Who can resist playing with kittens? Then they retaliate by grabbing the victim with their tiny little claws, which function like plowshares that sow the seed (B. henselae) into the victim’s skin.
There will usually be a recognizable sore or inflamed papule at the site of the scratch, as shown in Figure 3. The scratch will fade as the papule develops but may still be visible (Figure 4, a papule in the middle of a cat scratch that is still faintly visible on the wrist of a child with a swollen axillary node as seen in Figure 5, or may be hidden in an unusual place, like the fingertip shown in Figure 6). Occasionally, one may see two CSD papules within the same scratch mark (Figure 7). Occasionally, one may see two CSD papules within the same scratch mark, like in Figure 7. Of course, the regional node swells when the organism is carried there via the lymphatic system, which then often suppurates.
Figure 4 . A cat scratch disease papule in the middle of a faint, healed scratch. Image: James H. Brien, DO. 
Figure 5 . The patient with cat scratch disease seen in Figure 4 with right axillary adenopathy. Image: James H. Brien, DO. 
Figure 6 . A cat scratch site with a papule on the tip of the 5th finger. Image: James H. Brien, DO. 
Figure 7 . Two cat scratch disease papules on a faint, healed scratch. Courtesy of the J. W. Bass Collection. TIP: When an infection causes swelling with erythematous, shiny overlying skin, as shown in Figure 8, it almost always means underlying pus. When this happens in a patient with CSD, and removal of the pus is desired, doing so by needle aspiration, like in Figure 9, is the preferred method. If an incision and drainage is done, there is a great likelihood that it will continue to drain, creating a chronic draining fistula, as shown in Figures 10 and 11.
Figure 8 . Shiny erythematous overlying skin means underlying pus. Courtesy of J.W. Bass collection. 
Figure 9 . Cat scratch puss aspirated from the node seen in Figure 8 by needle aspiration. Courtesy of J.W. Bass collection. 
Figure 10 . A chronic draining incision and drainage site of a cat scratch disease node in a patient's neck. Image: James H. Brien, DO. 
Figure 11 . Closeup of a chronic draining incision and drainage site of a cat scratch disease node in a patient's neck. Image: James H. Brien, DO. For medical therapy, according to Nelson’s 2024 (30th Edition) Pediatric Antimicrobial Therapy, page 69, the preferred treatment for uncomplicated CSD is oral azithromycin, and for invasive disease; hepatosplenic (see March 2002 column) and osteomyelitis (see August 2006 and December 2009) a combination of gentamicin and trimethoprim/sulfamethoxazole and rifampin. For central nervous system disease, which I have never seen, the recommendation is the same combination except instead of rifampin, ceftriaxone is used.
NOTE: I might point out a discrepancy in Dr. Nelson’s book; it states the use of incision and drainage of suppurative nodes; it should be drained by needle aspiration, NOT incision and drainage.
Mycobacterium lepraemurium, one of the main agents of feline leprosy (which I have never seen), is a disease of cats, resulting in subcutaneous nodules and ulcerative lesions caused by the bite of an infected animal, usually another cat or rodent, with a distribution throughout the world. So far, there are no documented human cases reported.
Staphylococcus aureus is the bacteria responsible for most soft tissue abscesses. These can be drained by incision followed by treatment with an anti-staph antibiotic. The choice is usually made to cover both MRSA and methicillin-suseptible S. aureus until culture and sensitivities are known. Trimethoprim/sulfamethoxazole or clindamycin (if the child can take oral capsules, as the taste of the suspension is often rejected by the patient) can be used. Oftentimes, drainage alone will resolve the infection. If not, further therapy should be based on culture and sensitivity results.
Toxoplasma gondii is the causative agent of toxoplasmosis, an illness caused by a parasite that typically causes minimal to no symptoms in those with an intact immune system. It can be acquired by eating infected, undercooked meat or by contact with cat feces (the connection to this case). In pediatrics, we usually encounter this disease as a congenital infection. Acquired toxoplasmosis can result in lymphadenopathy without abscess, along with general influenza-like symptoms, and would likely go undiagnosed, but may be lethal if the patient is immunocompromised. (Columnist note: The “sister publication” to Infectious Diseases in Children is Infectious Disease News. My very first column was “Congenital Toxoplasmosis in premature triplets” in Infectious Disease News in December 1988).
Columnist comments
I want to thank Dr. Michael Cater, MD, of Orange County, California, for providing this interesting cluster of CSD in a single family. Dr. Cater has contributed many cases published in this column, and has my great gratitude.
Interestingly, my first column for Infectious Diseases in Children was in April 1989. It was a common case of CSD. After that, 9 more separate cases demonstrating various complications of CSD appeared (January 1994, May 1996, February 1999, March 2002, August 2006, December 2009, November 2010, October 2015, and the most recent being in August 2020, which included a tribute to Andy Margileth, MD, FAAP, who was a pioneer of CSD and helped raise our attention to this infectious disease many decades ago). Dr. Margileth had just turned 100 years old the month before that column. In the months leading up to his centennial birthday, I was helping Norah O’Donnell, the anchor of “CBS Evening News” and her team by providing the historic information along with many of the visuals needed for them to feature Andy in their “Profiles In Service” series. (My connection with Norah was that I was the O’Donnell family pediatrician when her father and I were stationed at Brooke Army Medical Center in the mid-1980s, where her father was the Chief of Preventive Medicine. They were also our neighbors a few houses away.)
The episode was to be aired on “CBS Evening News” around Andy’s birthday in July 2020. However, the COVID-19 pandemic had started and the feature was put off due to strict clinic access restrictions. By the summer of 2021, the restrictions were lifted, and the production resumed. It then celebrated the career of a 101-year-old pediatrician who was still seeing patients. This tribute can be seen here: https://www.cbsnews.com/video/101-year-old-pediatrician-pushes-off-retirement/.
In 2023, Andy retired from practice at age 103 and died at age 104 years on Aug. 2, 2024. There is an ongoing, long-standing annual research award given by the Uniformed Services Section of the American Academy of Pediatrics in Andy’s honor (The Margileth Award, representing the Navy). Other research awards created at the same time by the uniformed services included the Army’s Bruton Award and the Air Force’s Johnson Award (see the August 2020 column for details). Since then, several other military eponymous awards have been added.
Please keep in touch: jhbrien@aol.com.