Peripheral neuropathy is one such rare complication of KFD [2]. Limb paresis secondary to involvement of the brachial plexus was reported in a 22-year-old female with KFD [3]. Similarly, KFD may rarely affect the eye, resulting in panuveitis [4]. The disease may also cause ocular vasculitis and subretinal macular infiltrates. Patients with panuveitis may require methotrexate therapy.

In addition, rare complications involving the CNS may occur. For instance, meningitis has been reported in some cases [5]. Aseptic encephalitis has also been occasionally reported. Other patients have presented with cerebellar ataxia.

Cardiac complications such as tamponade may also rarely occur. KFD may additionally result in axillary lymphadenopathy [6]. Isolated mediastinal lymphadenopathy has also been reported [7], and the mesenteric lymph nodes may rarely be involved [8].

KFD may also result in acute renal failure [9]. Hepatitis is another rare complication. In addition, KFD may appear as SLE [10]. Hemophagocytic syndrome has also been reported as a complication of the disease [11]. The lungs may additionally be affected in rare cases, resulting in interstitial lung disease. The pleura may also be affected, leading to pleural effusion [12].

Rarely, KFD may occur following Hodgkin's lymphoma [13]. Similarly, Still's disease may be complicated by the appearance of KFD [14]. KFD may also infrequently occur following immunizations. For instance, the Japanese encephalitis virus vaccine, as well as the HPV vaccine, have been implicated as possible triggers of KFD [15]. KFD may also occasionally follow stem cell transplantation [16].

The above examples clearly detail the rare complications of KFD. Physicians should consider KFD in the differential diagnosis of patients presenting with these manifestations.